Risk Factors of Failure in 228 Periprosthetic Distal Femur Fractures: A Multicenter Study.

OBJECTIVES: To identify risk factors of reoperation to promote union or to address deep surgical-site infection (DSSI) in periprosthetic distal femur fractures treated with lateral distal femoral locking plates (LDFLPs). DESIGN: Multicenter retrospective cohort study. SETTING: Ten level-I trauma centers. PATIENT SELECTION CRITERIA: Patients with Orthopaedic Trauma Association/Association of Osteosynthesis (OTA/AO) 33A or 33C periprosthetic distal femur fractures who underwent surgical fixation between January 2012 and December 2019 exclusively using LDFLPs were eligible for inclusion. Patients with pathologic fractures or with follow-up less than 3 months without an outcome event (unplanned reoperation to promote union or for deep surgical infection) before this time point were excluded. Fracture fixation constructs used medial plates, intramedullary nails, or hybrid fixation constructs were excluded from analysis. OUTCOME MEASURES AND COMPARISONS: To examine the influence of patient demographics, injury characteristics, and features of the fracture fixation construct on the occurrence of unplanned reoperation to promote union or to address a DSSI. RESULTS: There was an 8.3% rate (19/228) of unplanned reoperation to promote union. Predictive factors for the need for reoperation to promote union included increasing body mass index (odds ratio [OR] = 1.09; 95% confidence interval [CI]: 1.02-1.16; P = 0.01), increasing number of screws in the distal fracture segment (OR = 1.73; 95% CI: 1.06-2.95; P = 0.03), and decreasing proportion of proximal segment screws that are locking (OR = 0.17; 95% CI: 0.03-0.70; P = 0.02) There was a 4.8% rate (11/228) of reoperation to address DSSI. There were no statistically significant predictive factors identified as risk factors of the need for reoperation to address DSSI ( P > 0.05). CONCLUSIONS: 8.3% of periprosthetic distal femur fractures treated at 10 centers with LDFLPs underwent unplanned reoperation to promote union. Increasing patient body mass index and increasing number of screws in the distal fracture segment were found to be predictive factors, whereas increased locking screws in the proximal segment were found to be protective. 4.8% of patients in this cohort underwent reoperation to address DSSI. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Resident Synovial Macrophages in Synovial Fluid: Implications for Immunoregulation in Infectious and Inflammatory Arthritis.

Objectives: Resident synovial macrophages (RSM) provide immune sequestration of the joint space and are likely involved in initiation and perpetuation of the joint-specific immune response. We sought to identify RSM in synovial fluid (SF) and demonstrate migratory ability, in additional to functional changes that may perpetuate a chronic inflammatory response within joint spaces. Methods: We recruited human patients presenting with undifferentiated arthritis in multiple clinical settings. We used flow cytometry to identify mononuclear cells in peripheral blood and SF. We used a novel transwell migration assay with human ex-vivo synovium obtained intra-operatively to validate flow cytometry findings. We used single cell RNA-sequencing (scRNA-seq) to further identify macrophage/monocyte subsets. ELISA was used to evaluate the bone-resorption potential of SF. Results: We were able to identify a rare population of CD14dim, OPG+, ZO-1+ cells consistent with RSM in SF via flow cytometry. These cells were relatively enriched in the SF during infectious processes, but absolutely decreased compared to healthy controls. Similar putative RSM were identified using ex vivo migration assays when MCP-1 and LPS were used as migratory stimulus. scRNA-seq revealed a population consistent with RSM transcriptionally related to CD56+ cytotoxic dendritic cells and IDO+ M2 macrophages. Conclusion: We identified a rare cell population consistent with RSM, indicating these cells are likely migratory and able to initiate or coordinate both acute (septic) or chronic (autoimmune or inflammatory) arthritis. RSM analysis via scRNA-seq indicated these cells are M2 skewed, capable of antigen presentation, and have consistent functions in both septic and inflammatory arthritis.

Technical Factors Contributing to Nonunion in Supracondylar Distal Femur Fractures Treated With Lateral Locked Plating: A Risk-Stratified Analysis.

OBJECTIVE: To identify technical factors associated with nonunion after operative treatment with lateral locked plating. DESIGN: Retrospective cohort study. SETTING: Ten Level I trauma centers. PATIENT SELECTION CRITERIA: Adult patients with supracondylar distal femur fractures (OTA/AO type 33A or C) treated with lateral locked plating from 2010 through 2019. OUTCOME MEASURES AND COMPARISONS: Surgery for nonunion stratified by risk for nonunion. RESULTS: The cohort included 615 patients with supracondylar distal femur fractures. The median patient age was 61 years old (interquartile range: 46 -72years) and 375 (61%) were female. Observed were nonunion rates of 2% in a low risk of nonunion group (n = 129), 4% in a medium-risk group (n = 333), and 14% in a high-risk group (n = 153). Varus malreduction with an anatomic lateral distal femoral angle greater than 84 degrees, was associated with double the odds of nonunion compared to those without such varus [odds ratio, 2.1; 95% confidence interval (CI), 1.1-4.2; P = 0.03]. Malreduction by medial translation of the articular block increased the odds of nonunion, with 30% increased odds per 4 mm of medial translation (95% CI, 1.0-1.6; P = 0.03). Working length increased the odds of nonunion in the medium risk group, with an 18% increase in nonunion per 10-mm increase in working length (95% CI, 1.0-1.4; P = 0.01). Increased proximal screw density was protective against nonunion (odds ratio, 0.71; 95% CI, 0.53-0.92; P = 0.02) but yielded lower mRUST scores with each 0.1 increase in screw density associated with a 0.4-point lower mRUST (95% CI, -0.55 to -0.15; P < 0.001). Lateral plate length and type of plate material were not associated with nonunion. ( P > 0.05). CONCLUSIONS: Malreduction is a surgeon-controlled variable associated with nonunion after lateral locked plating of supracondylar distal femur fractures. Longer working lengths were associated with nonunion, suggesting that bridge plating may be less likely to succeed for longer fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Health literacy in rotator cuff repair: a quantitative assessment of the understandability of online patient education material.

Background: The American Medical Association and National Institutes of Health recommend online health information be written at a 6th grade or lower reading level for clear understanding. While syntax reading grade level has previously been utilized, those analyses do not determine whether readers are processing key information (understandability) or identifying available actions to take (actionability). The Patient Education Materials Assessment Tool (PEMAT-P) is a method to measure the understandability and actionability of online patient education materials. The purpose of this study was to evaluate online resources regarding rotator cuff repair utilizing measures of readability, understandability, and actionability. Methods: The search term "rotator cuff surgery" was used in two independent online searches to obtain the top 50 search results. The readability of included resources was quantified using valid objective algorithms: Flesch-Kincaid Grade-Level, Simple Measure of Gobbledygook grade, Coleman-Liau Index, and Gunning Fog Index. The PEMAT-P form was used to assess actionability and understandability. Results: A total of 49 unique websites were identified to meet our inclusion criteria and were included in our analysis. The mean Flesch-Kincaid Grade Level graded materials at a 10.6 (approximately a 10th grade reading level), with only two websites offering materials at a 6th grade reading level or below. The remaining readability studies graded the mean reading level at high school or greater, with the Gunning Fog Index scoring at a collegiate reading level. Mean understandability and actionability scores were 64.6% and 29.5%, respectively, falling below the 70% PEMAT score threshold for both scales. Fourteen (28.6%) websites were above the threshold for understandability, while no website (0%) scored above the 70% threshold for actionability. When comparing source categories, commercial health publishers provided websites that scored higher in understandability (P < .05), while private practice materials scored higher in actionability (P < .05). Resources published by academic institutions or organizations scored lower in both understandability and actionability than private practice and commercial health publishers (P < .05). No readability, understandability, or actionability score was significantly associated with search result rank. Conclusion: Overall, online patient education materials related to rotator cuff surgery scored poorly with respect to readability, understandability, and actionability. Only two (4.1%) of the patient education websites scored at the American Medical Association and National Institutes of Health recommended reading level. Fourteen (28.6%) scored above the 70% PEMAT score for understandability; however, no website met the threshold for actionability.

Nail Plate Combination Fixation Versus Lateral Locked Plating for Distal Femur Fractures: A Multicenter Experience.

OBJECTIVES: To (1) report on clinical, radiographic, and functional outcomes after nail-plate fixation (NPF) of distal femur fractures and (2) compare outcomes after NPF with a propensity matched cohort of fractures treated with single precontoured lateral locking plates. DESIGN: Multicenter retrospective cohort study. SETTING: Ten Level 1 trauma centers. PATIENTS/PARTICIPANTS: Patients with OTA/AO 33A or 33C fractures. INTERVENTION: Fixation with (1) retrograde intramedullary nail combined with lateral locking plate (n = 33) or (2) single precontoured lateral locking plate alone (n = 867). MAIN OUTCOME MEASUREMENTS: The main outcomes of interest were all-cause unplanned reoperation and presence of varus collapse at final follow-up. RESULTS: One nail-plate patient underwent unplanned reoperation excluding infection and 2 underwent reoperation for infection at an average of 57 weeks after surgery. No nail-plate patients required unplanned reoperation to promote union and none exhibited varus collapse. More than 90% were ambulatory with no or minimal pain at final follow-up. In comparison, 7 of the 30 matched lateral locked plating patients underwent all-cause unplanned reoperation excluding infection (23% vs. 3%, P = 0.023), and an additional 3 lateral locked plating patients were found to have varus collapse on final radiographs (10% vs. 0%, P = 0.069). CONCLUSIONS: Despite a high proportion of high-energy, open, and comminuted fractures, no NPF patients underwent unplanned reoperation to promote union or demonstrated varus collapse. Propensity score matched analysis revealed significantly lower rates of nonunion for NPF compared with lateral locked plating alone. Larger studies are needed to identify which distal femur fracture patients would most benefit from NPF. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Characteristics and Long-Term Outcome of Surgically Managed High-Grade Extremity Chondrosarcoma.

Background: Dedifferentiated chondrosarcoma (DCS) is a highly malignant variant that portends a poor prognosis. Although factors such as clinico-pathological characteristics, surgical margin, and adjuvant modalities likely play a role in overall survival, debate continues with varying results on the importance of these indicators. The purpose of this study is (1) To delineate the characteristics, local recurrence (LR), and survival of patients with intermediate (IGCS), high (HGCS) and dedifferentiated (DCS) chondrosarcoma of the extremity by utilizing detailed cases at one tertiary institution. (2) To assess survival between high grade chondrosarcoma and DCS utilizing a less detailed but large cohort from the Surveillance, Epidemiology, and End Results (SEER) database. Methods: Twenty-six cases of high-grade (conventional FNCLCC grades 2 and 3, dedifferentiated) chondrosarcoma were identified from an ongoing prospective cohort of 630 sarcoma patients managed surgically at a tertiary referral university hospital between 9/1/2010-12/30/2019. A retrospective review of demographics, tumor characteristics, surgical procedure, treatment course, and survival data was performed to determine prognostic factors for survival. An additional 516 cases of chondrosarcoma were identified from the SEER database. Using the Kaplan-Meier method, both the large database and case series were evaluated, and estimated cause-specific survival was calculated at 1, 2, and 5 years. Results: There were 12 IGCS, 5 HGCS, and 9 DCS patients in the single institution cohort. DCS had a higher stage at diagnosis (p=0.04). Limb salvage was the most common procedure performed in every group (11/12 IGCS, 5/5 HGCS, and 7/9 DCS; p=0.56). Margins included 8/12 wide and 3/12 intralesional for IGCS. For HGCS, there were 3/5 wide, 1/5 marginal, and 1/5 intralesional. A majority of DCS margins were wide (8/9) with only 1 marginal. There was no difference of associated margins between the groups (p=0.85), however there was a difference when margins were classified based on numerical measurement (IGCS: 0.125cm (0.1-0.35); HGCS: 0cm (0-0.1); DCS: 0.2cm (0.1-0.5); p=0.03). The overall median follow-up was 26 months (IQR:16.1-70.8). The time interval from resection to death was lower in DCS (11.5 months (10.7-12.2)), followed by IGCS (30.3 months (16.2-78.2)), and HGCS (55.1 months (32.0-78.2; p=0.047). LR occurred in 5/9 DCS, 1/5 HGCS, and 1/14 IGCS patients. Of the DCS patients only 2/6 who received systemic therapy had LR, while all 3/3 who did not receive systemic therapy had LR. Overall systemic therapy and radiation did not impact incidence of LR (p=0.67; p=0.34). However, patients who had LR were 17.5 times more likely to die within one year (HR=17.5, 95%CI (1.01-303.7), p=0.049), after adjusting for the age at the surgery. There was no correlation with the utilization of systemic therapy, radiation therapy, or margin and overall survival (p=0.63, p=0.52, p=0.74). In the SEER patient cohort, 149 cases (28.9%) were DCS and 367 (71.1%) were HGCS. At final follow-up, 49.6% (n=256) of the cohort had a cause of death due to chondrosarcoma. HGCS was associated with higher chance of 1-year survial (p<0.001), 2-year survival (p<0.001), 5-year survival (p<0.001), and overall survival (p<0.001). Additionally, decreased survival was associated with metastatic disease at presentation (p=0.01). Overall limb salvage was most utilized for both HGCS (76.5%) and DCS (74.3%). In regard to limb salvage vs. amputation, there was no difference in survival at 1 year (p=0.10) or 2 year (p=0.13) between the groups, however those who underwent limb salvage procedure had a significantly better chance of survival at 5 years when compared to amputation (HR=1.49 (1.11-1.99); p=0.002). Conclusion: High-grade chondrosarcoma remains a fatal disease in many patients, particularly if associated with dedifferentiated subtype. Interestingly, all (100%) DCS patients who did not receive systemic therapy had LR. However, chemotherapy and radiation did not significantly increase survival. In this case series and large database study, HGCS had the smallest surgical margin, but with the longest time interval for both LR and death. Additionally, using the SEER database, DCS and amputation had worse prognosis at the 5-year survival time. Further studies on valuable prognostic influences as well as earlier identification of this rare disease may help in developing better management options. Level of Evidence: III.

Predictors of Deep Infection After Distal Femur Fracture: A Multicenter Study.

OBJECTIVES: To identify potentially modifiable risk factors for deep surgical site infection after distal femur fracture. DESIGN: Multicenter retrospective cohort study. SETTING: Ten Level-I trauma centers. PATIENTS/PARTICIPANTS: Patients with OTA/AO 33A or C distal femur fractures (n = 1107). INTERVENTION: Surgical fixation of distal femur fracture. MAIN OUTCOME MEASUREMENT: The outcome of interest was deep surgical site infection. RESULTS: There was a 7% rate (79/1107) of deep surgical site infection. In the multivariate analysis, predictive factors included alcohol abuse [odds ratio (OR) = 2.36; 95% confidence interval (CI), 1.17-4.46; P = 0.01], intra-articular injury (OR = 1.73; 95% CI, 1.01-3.00; P = 0.05), vascular injury (OR = 3.90; 95% CI, 1.63-8.61; P < 0.01), the use of topical antibiotics (OR = 0.50; 95% CI, 0.25-0.92; P = 0.03), and the duration of the surgery (OR = 1.15 per hour; 95% CI, 1.01-1.30; P = 0.04). There was a nonsignificant trend toward an association between infection and type III open fracture (OR = 1.73; 95% CI, 0.94-3.13; P = 0.07) and lateral approach (OR = 1.60; 95% CI, 0.95-2.69; P = 0.07). The most frequently cultured organisms were methicillin-resistant Staphylococcus aureus (22%), methicillin-sensitive Staphylococcus aureus (20%), and Enterobacter cloacae (11%). CONCLUSIONS: Seven percent of distal femur fractures developed deep surgical site infections. Alcohol abuse, intra-articular fracture, vascular injury, and increased surgical duration were risk factors, while the use of topical antibiotics was protective. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Risk Factors for Reoperation to Promote Union in 1111 Distal Femur Fractures.

OBJECTIVES: To identify modifiable and nonmodifiable risk factors for reoperation to promote union after distal femur fracture. DESIGN: Multicenter retrospective cohort study. SETTING: Ten Level-I trauma centers. PATIENTS/PARTICIPANTS: Patients with OTA/AO 33A or C distal femur fractures (n = 1111). INTERVENTION: Surgical fixation of distal femur fracture. Fixation constructs were classified as lateral plate, dual plate, nail, or nail plate combination. MAIN OUTCOME MEASUREMENTS: The outcome of interest was unplanned reoperation to promote union. RESULTS: There was an 11% (121/1111) rate of unplanned reoperation to promote union. In the multivariate analysis, predictive factors included body mass index [odds ratio (OR) = 1.18; 95% confidence interval (CI), 1.06-1.32; P < 0.01], intra-articular fracture (OR = 1.57; 95% CI, 1.01-2.45; P = 0.04), type III open injury (OR = 2.29; 95% CI, 1.41-3.72; P < 0.01), the presence of medial comminution (OR = 1.85; 95% CI, 1.14-3.06; P = 0.01), and medial translation on postoperative radiographs (OR = 1.23 per one 10th of condylar width; 95% CI, 1.01-1.48; P = 0.03). Construct type was not significantly predictive. CONCLUSIONS: Eleven percent of distal femur fractures underwent unplanned reoperation to promote union. Body mass index, intra-articular fracture, type III open injury, medial comminution, and medial translation on postoperative radiographs were predictive factors. Construct type was not associated with unplanned reoperation; however, this conclusion was limited by small numbers in the dual plate and nail plate groups. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Spin in the Abstracts of Meta-analyses and Systematic Reviews: Midshaft Clavicle Fracture.

OBJECTIVES: Spin is a reporting bias that presents the beneficial effect of an experimental treatment as greater than what is found in the results of the study. This bias can result in patient care recommendations that are more subjective than objective. The purpose of this study is to identify the prevalence of spin in meta-analysis and systematic review abstracts regarding treatment of midshaft clavicle fractures. METHODS: Electronic libraries (MEDLINE, Embase, Web of Science, Google Scholar) were systematically searched. Meta-analyses and systematic reviews regarding treatment of midshaft clavicular fractures were analyzed. The nine most severe types of spin commonly found in abstracts were used as an evaluation tool to assess the articles. Other variables analyzed include year of publication, journal impact factor, number of citations, and methodologic quality according to A Measurement Tool to Assess Systematic Reviews (AMSTAR-2). RESULTS: The database search resulted in 401 articles, of which 53 met inclusion criteria. After review, it was found that 52.8% (28/53) of the included articles contained spin within the abstract. Of the nine most severe types of spin found in abstracts, type 3 spin ("selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention") was found to be the most prevalent 28.3% (15/53). CONCLUSION: This study demonstrated the presence of spin in the majority of meta-analyses and systematic review abstracts pertaining to midshaft clavicular fractures. Orthopedic surgeons should be aware and recognize spin as they review articles when deciding the treatment course for such injuries. LEVEL OF EVIDENCE: Level 3. See Instructions for Authors for a complete description of levels of evidence.

Can Patients Read, Understand, and Act on Online Resources for Anterior Cruciate Ligament Surgery?

Background: Patients undergoing elective procedures often utilize online educational materials to familiarize themselves with the surgical procedure and expected postoperative recovery. While the Internet is easily accessible and ubiquitous today, the ability of patients to read, understand, and act on these materials is unknown. Purpose: To evaluate online resources about anterior cruciate ligament (ACL) surgery utilizing measures of readability, understandability, and actionability. Study Design: Cross-sectional study; Level of evidence, 4. Methods: Using the term "ACL surgery," 2 independent searches were performed utilizing a public search engine (Google.com). Patient education materials were identified from the top 50 results. Audiovisual materials, news articles, materials intended for advertising or medical professionals, and materials unrelated to ACL surgery were excluded. Readability was quantified using the Flesch Reading Ease, Flesch-Kincaid Grade Level, Simple Measure of Gobbledygook, Coleman-Liau Index, Automated Readability Index, and Gunning Fog Index. The Patient Education Materials Assessment Tool for Printable Materials (PEMAT-P) was utilized to assess the actionability and understandability of materials. For each online source, the relationship between its Google search rank (from first to last) and its readability, understandability, and actionability was calculated utilizing the Spearman rank correlation coefficient (ρS). Results: Overall, we identified 68 unique websites, of which 39 met inclusion criteria. The mean Flesch-Kincaid Grade Level was 10.08 ± 2.34, with no website scoring at or below the 6th-grade level. Mean understandability and actionability scores were 59.18 ± 10.86 (range, 33.64-79.17) and 34.41 ± 22.31 (range, 0.00-81.67), respectively. Only 5 (12.82%) and 1 (2.56%) resource scored above the 70% adequate PEMAT-P threshold mark for understandability and actionability, respectively. Readability (lowest P value = .103), understandability (ρS = -0.13; P = .441), and actionability (ρS = 0.28; P = .096) scores were not associated with Google rank. Conclusion: Patient education materials on ACL surgery scored poorly with respect to readability, understandability, and actionability. No online resource scored at the recommended reading level of the American Medical Association or National Institutes of Health. Only 5 resources scored above the proven threshold for understandability, and only 1 resource scored above it for actionability.

The Relationship Between Lesion Size and Load to Failure After Stabilization of Simulated Metastatic Lesions of the Proximal Femur.

Background: As overall cancer survival continues to improve, the incidence of metastatic lesions to the bone continues to increase. The subsequent skeletal related events that can occur with osseous metastasis can be debilitating. Complete and impending pathologic femur fractures are common with patients often requiring operative fixation. However, the efficacy of an intramedullary nail construct, on providing stability, continue to be debated. Therefore, the purpose of this study was to utilize a synthetic femur model to determine 1) how proximal femur defect size and cortical breach impact femur load to failure (strength) and stiffness, and 2) and how the utilization of an IMN, in a prophylactic fashion, subsequently alters the overall strength and stiffness of the proximal femur. Methods: A total of 21 synthetic femur models were divided into four groups: 1) intact (no defect), 2) 2 cm defect, 3) 2.5 cm defect, and 4) 4 cm defect. An IMN was inserted in half of the femur specimens that had a defect present. This procedure was performed using standard antegrade technique. Specimens were mechanically tested in offset torsion. Force-displacement curves were utilized to determine each constructs load to failure and overall torsional stiffness. The ultimate load to failure and construct stiffness of the synthetic femurs with defects were compared to the intact synthetic femur, while the femurs with the placement of the IMN were directly compared to the synthetic femurs with matching defect size. Results: The size of the defect invertedly correlated with the load the failure and overall stiffness. There was no difference in load to failure or overall stiffness when comparing intact models with no defect and the 2 cm defect group (p=0.98, p=0.43). The 2.5 cm, and 4.5 cm defect groups demonstrated significant difference in both load to failure and overall stiffness when compared to intact models with results demonstrating 1313 N (95% CI: 874-1752 N; p<0.001) and 104 N/mm (95% CI: 98-110 N/mm; p=0.03) in the 2.5 cm defect models, and 512 N (95% CI: 390-634 N, p<0.001) and 21 N/mm (95% CI: 9-33 N/mm, p<0.001) in the models with a 4 cm defect. Compared to the groups with defects, the placement an IMN increased overall stiffness in the 2.5 cm defect group (125 N/mm; 95% CI:114-136 N/mm; p=0.003), but not load to failure (p=0.91). In the 4 cm defect group, there was a significant increase in load to failure (1067 N; 95% CI: 835-1300 N; p=0.002) and overall stiffness (57 N/mm; 95% CI:46-69 N/mm; p=0.001). Conclusion: Prophylactic IMN fixation significantly improved failure load and overall stiffness in the group with the largest cortical defects, but still demonstrated a failure loads less than 50% of the intact model. This investigation suggests that a cortical breach causes a loss of strength that is not completely restored by intramedullary fixation. Level of Evidence: II.

Does Isolated Unilateral Hip or Knee Osteoarthritis Lead to Adverse Changes in Extremity Composition?

Background: While muscle atrophy is a function of normal aging, loss of muscle in the setting of hip and knee osteoarthritis (OA) has been observed using radiographic studies. There is limited data available regarding changes in extremity composition using bioimpedance (BIA). The purpose of this study was to assess the changes in extremity composition in patients with isolated, unilateral hip or knee OA using BIA. Methods: Patients presenting to our institution's adult reconstruction clinic from February 2020 to April 2021 were retrospectively reviewed to identify those with isolated, unilateral hip and knee OA. The InBody 770 Body Composition Analyzer (InBody USA, Cerritos, California) was used to perform a complete body composition assessment, per protocol. Lean extremity mass (LEM), fat mass (FM), intracellular water (ICW), extremity body water (EBW = ICW + extracellular water (ECW)) and phase angle (PA) were determined. Differences between the affected (OA) and unaffected (no OA) extremities were compared using t-tests. Results: 38 patients had isolated hip OA. The mean age was 60.8 (±11.7) years, mean BMI was 31.7 (±6.8) kg/m2, and 39.5% were female. LEM, FM, EBW, ICW, and PA were significantly decreased in the hip OA extremity (LEM: 20.0 vs. 20.4 kg, p=0.0008, FM: 8.8 vs. 8.9 kg, p=0.0049, EBW: 15.7 vs 16.0, p=0.0011, ICW: 9.5 vs. 9.7 L, p=0.0004, PA: 4.5 vs 4.9º, p<0.0001). There were 25 patients with isolated knee OA. Mean age was 62.8 (±11.3) years, mean BMI was 33.6 (±6.9) kg/m2, and 52.0% were female. FM and PA were significantly lower in the knee OA extremity (11.3 vs 11.4 kg, p=0.0291, 4.5 vs 4.9º, p<0.0001). There were no significant differences in LEM, EBW, and ICW between the knee OA extremity and the unaffected extremity. Conclusion: Patients with isolated, unilateral hip OA had decreased LEM, FM, EBW, and ICW in the affected extremity. Both unilateral hip and knee OA was associated with decreased PA, suggestive of greater underlying dysfunction in muscle or cellular performance. Further study is needed to better define when these abnormalities develop, how they progress over time, and the impact of targeted interventions in reversing these changes. Level of Evidence: III.

Total Hip Arthroplasty: Direct Anterior Approach Versus Posterior Approach in the First Year of Practice.

Background: The direct anterior approach (DAA) for total hip arthroplasty (THA) has been popularized as a less invasive technique, however outcomes within the first year of practice after fellowship have not been investigated. The primary aim was to determine differences in complications and outcomes between DAA and posterior approach (PA) in the first year of practice. The secondary aim was to determine if there was a learning curve factor in DAA and PA after fellowship training. Methods: THA cases performed by two surgeons during their first year of practice were reviewed. Overall, 181 THAs (91 DAA, 90 PA) in 168 patients, were performed. Intraoperative differences (blood loss, operative time), hospital stay, complications, reoperations, and revisions were compared. Results: Overall surgical complications were similar between DAA and PA (11% vs. 9%, p=0.64), but complication profiles were different: dislocation (1% vs. 4%, p=0.17), intraoperative femoral fracture (2% vs. 1%, p=0.32), postoperative periprosthetic fractures (2% vs. 3%, p=0.64). neuropraxia (3% vs. 0%, p=0.08). There was no difference in rate of reoperation (1% vs. 3%, p=0.31). There was a difference in rate of revision at final follow-up (0% vs. 6%, p=0.02). DAA consisted of longer operative time (111 vs. 99 minutes; p<0.001), however was only significant in the first 50 cases (p<0.001), while the subsequent cases were similar (p=0.31). There was no difference in the first 50 cases compared to the subsequent cases for either approach regarding blood loss, complications, reoperations, or revisions. Conclusion: DAA and PA for THA performed within the first year of practice exhibit similarly low complication rates, but complication profiles are different. In our series, PA did demonstrate a higher risk of revision at final follow-up. A learning curve is not unique to the DAA. Both DAA and PA THA exhibited a learning curve in the first 50 cases performed at the start of a surgeon's practice. Level of Evidence: III.

The Impact of Orthopaedic Surgical Training on Body Composition.

Background: Residency is known to consist of rigorous training that has contributed to increased rates of resident burn out, depression, and suicide. There have been recent efforts to attempt to combat and solve the rising levels of mental health concerns amongst physicians and physicians in training. While studies have examined the adverse effects of medical training on mental health, few have examined the associated changes in physical health. This study aimed to identify and compare baseline body composition and hand grip strength of orthopaedic surgery residents. The second aim was to identify and compare changes that may occur over the course of the training program. Methods: First year orthopaedic surgery residents ("interns") were recruited to undergo body composition measurements via bioimpedance analysis (BIA) during their first, third, and twelfth month of post-graduate training. At each interval, three hand-grip-strength measurements per hand were captured. Additionally, orthopaedic surgery residents who had already completed their first year ("non-interns") were recruited to undergo baseline and 12-month BIA for comparison. Results: Six interns and six non-interns were recruited. The interns lost 2.88 ± 4.26 kg (-3.31% ± 4.75%) of their initial body mass with most of the loss being body fat mass (1.97 ± 2.62 kg) by three months. Interns recovered a fair amount of mass loss by 12 months with a net change of -0.78 ± 3.14 kg (-1.09% ± 3.90%). Non-interns experienced an overall net weight gain (1.20 ± 3.64 kg; 1.68% ± 5.55%) over the same period. Intern HGS changed by -1.92 ± 2.49 kg and 3.39 ± 2.34 kg at 3- (n=6) and 12-months (n=3), respectively. Conclusion: This study demonstrates that there is an appreciable decrease in overall body mass, lean tissue mass, and body fat throughout the orthopaedic resident's intern year. The results demonstrate an initial fall in each body metric and strength by 3-months followed by partial recovery by 12-months. This pattern contrasts the average gain of body mass in each measured metric by non-interns. This study is limited by population sizes and by incompleteness of HGS data. Level of Evidence: II.

Do Pediatric Hospitals Improve Operative Efficiency?

Background: In recent years there has been a push towards developing free standing pediatric facilities to provide care specifically towards pediatric patients. The purpose of this study was to determine if moving pediatric cases from a general hospital to a dedicated pediatric facility improved the quality and efficiency of surgical procedures. Methods: A retrospective review of pediatric patients undergoing posterior spinal fusion (PSF) was performed. All procedures were performed by one orthopaedic surgeon (SLW) from 2015 to 2019. The procedures were performed at a general hospital (GH) the first two years, and at a pediatric hospital (PH) the subsequent years. Data extracted included patient sex, age, and procedure type as well as procedure duration, operative turnover time, hospital length of stay, transfusion requirements, and operative delay. Exclusively pediatric adolescent idiopathic scoliosis (AIS) patients undergoing PSF were included due to the high volume and consistent surgical procedures therefore limiting confounding variables. Results: A total of five hundred PSF pediatric procedures were performed during the time period. After excluding non-adolescent idiopathic scoliosis cases, a total of 208 procedures were reviewed (105 at GH; 103 at PH). There was no statistical difference between the groups in regards to operative time (GH: 200 min, PH: 200 min; p=0.91), room turnover time (GH: 38 min, PH: 38 min; p=0.801), or rate of transfusion (GH: 20% PH: 30%; p=0.09). Length of stay was significantly shorter in the PH cohort compared to the GH cohort (4.35 vs. 3.84 days, p=0.0001). However, a smaller proportion of cases at the PH started on time compared to the GH (34% vs. 58%; p=0.0005). Conclusion: Overall, this study demonstrated that AIS procedures at the PH did show a statistically significant reduction in hospital length of stay. However, timely start of the procedure was less likely at this particular facility. Level of Evidence: III.

Web-Based Patient Educational Material on Osteosarcoma: Quantitative Assessment of Readability and Understandability.

BACKGROUND: Patients often turn to web-based resources following the diagnosis of osteosarcoma. To be fully understood by average American adults, the American Medical Association (AMA) and National Institutes of Health (NIH) recommend web-based health information to be written at a 6th grade level or lower. Previous analyses of osteosarcoma resources have not measured whether text is written such that readers can process key information (understandability) or identify available actions to take (actionability). The Patient Education Materials Assessment Tool (PEMAT) is a validated measurement of understandability and actionability. OBJECTIVE: The purpose of this study was to evaluate web-based osteosarcoma resources using measures of readability, understandability, and actionability. METHODS: Using the search term "osteosarcoma," two independent Google searches were performed on March 7, 2020 (by AGS), and March 11, 2020 (by TRG). The top 50 results were collected. Websites were included if they were directed at providing patient education on osteosarcoma. Readability was quantified using validated algorithms: Flesh-Kincaid Grade Ease (FKGE), Flesch-Kincaid Grade-Level (FKGL). A higher FKGE score indicates that the material is easier to read. All other readability scores represent the US school grade level. Two independent PEMAT assessments were performed with independent scores assigned for both understandability and actionability. A PEMAT score of 70% or below is considered poorly understandable or poorly actionable. Statistical significance was defined as P≤.05. RESULTS: Two searches yielded 53 unique websites, of which 37 (70%) met the inclusion criteria. The mean FKGE and FKGL scores were 40.8 (SD 13.6) and 12.0 (SD 2.4), respectively. No website scored within the acceptable NIH or AHA recommended reading level. Only 4 (11%) and 1 (3%) website met the acceptable understandability and actionability threshold. Both understandability and actionability were positively correlated with FKGE (ρ=0.55, P<.001; ρ=0.60, P<.001), but were otherwise not significantly associated with other readability scores. There were no associations between readability (P=.15), understandability (P=.20), or actionability (P=.31) scores and Google rank. CONCLUSIONS: Overall, web-based osteosarcoma patient educational materials scored poorly with respect to readability, understandability, and actionability. None of the web-based resources scored at the recommended reading level. Only 4 achieved the appropriate score to be considered understandable by the general public. Authors of patient resources should incorporate PEMAT and readability criteria to improve web-based resources to support patient understanding.

Total Knee Arthroplasty: A Quantitative Assessment of Online Patient Education Resources.

Background: Patients often turn to the online resources to learn about orthopedic procedures. As the rate of joint arthroplasty is projected to increase, the corresponding interest in relevant online education material will increase as well. The American Medical Association (AMA) and National Institutes of Health (NIH) recommend that publicly available online health information be written at the 6th grade or lower reading level to be fully understood by the average adult in the United States. Additionally, educational resources should be written such that readers can process key information (understandability) or identify available actions to take (actionability). The purpose of this study was to quantify the readability, understandability, and actionability of online patient educational materials regarding total knee arthroplasty (TKA). Methods: The most common Google™ search term utilized by the American public was determined to be "knee replacement". Subsequently two independent online searches (Google.com) were performed. From the top 50 search results, websites were included if directed at educating patients regarding TKA. Non-text websites (audiovisual), articles (news/research/industry), and unrelated resources were excluded. Readability was quantified using the following valid objective algorithms: Flesch-Kincaid Grade-Level (FKGL), Simple Measure of Gobbledygook (SMOG) grade, Coleman-Liau Index (CLI), and Gunning-Fog Index (GFI). PEMAT was utilized to assess understandability and actionability (0-100%; score ≥70% indicates acceptable scoring). The relationship between search rank with FKGL and PEMAT scores was quantified. Results: A total of 34 (68%) unique websites met inclusion criteria. The mean FKGL, SMOG, CLI, and GFI was 11.8±1.6, 11.1±1.2, 11.9±1.4, and 14.7±1.6, respectively. None of the websites scored within the acceptable NIH/AMA recommended reading levels. Mean understandability and actionability scores were 54.9±12.1 and 30.3±22.0. Only 5.9% (n=2) and 9.2% (n=1) of websites met the ≥70% threshold for understandability and actionability. Only 29.4% (n=10) sources used common language and only 26.9% (n=9) properly defined complicated medical terms. Based on website type, the mean understandability scores for academic institution, private practice, and health information publisher websites were 57.2±8.8%, 52.6±11.1%, and 54.3±15.3% (p=0.67). Readability (rho: -0.07; p=0.69), understandability (rho: -0.02; p=0.93), and actionability (rho: -0.22; p=0.23) scores were not associated with Google™ search rank. Conclusion: TKA materials scored poorly with respect to readability, understandability, and actionability. None of the resources scored within the recommended AMA/NIH reading levels. Only 5.9% scored adequately on understandability measures. Substantial efforts are needed to improve online resources to optimize patient comprehension and facilitate informed decision-making. Level of Evidence: III.

Does Anterior Impaction Affect Radiographic Outcomes of Pilon Fractures?

Background: The outcomes of pilon fractures are multifactorial. Anterior articular impaction requires sagittal plane correction (anterior distal tibia angle (ADTA)) with articular reduction. However, there is a risk of avascular necrosis of the articular fragments and postoperative tibiotalar arthritis. The purpose of this study was to determine if the presence of anterior impaction affects radiographic alignment after definitive fixation. Methods: Retrospective cohort study of patients who underwent operative management for pilon fractures at two academic, level 1 trauma centers between September 2005-September 2016. Fractures were categorized as having anterior impaction or no anterior impaction after review of preoperative radiographic and computer tomography imaging. Patient demographics and postoperative time to union was recorded. Quality of reduction was measured using (ADTA) (degrees), lateral distal tibia angle (LDTA) (degrees), and lateral talar station (LTS) (millimeters) from postoperative radiographs. Statistical analysis compared fracture patterns with anterior impaction to those without. Results: 208 patients met inclusion criteria. 132 fractures (63.4%) were determined to have anterior impaction. Cohorts were similar in demographics and medical comorbidities (p>0.05). Mean ADTA, LTDA, and LTS for the anterior impaction group 83.5°, 89.7°, and 2.4mm versus 84.6°, 89.9°, and 2.0mm in the group without anterior impaction. Cohorts significantly differed in ADTA(p=0.01), but not LDTA(p=0.12) or LTS(p=0.44). No significant differences were found between cohorts with infection (>0.05), nonunion(p=0.76), unplanned reoperation(p=0.56), or amputation(p=0.34). Conclusion: This study demonstrated no significant differences in the coronal or sagittal plane alignment when comparing definitively fixed pilon fractures with and without anterior impaction. Additional studies are needed to evaluate the longterm clinical impact of failing to restore ADTA. Level of Evidence: III.

Resident Participation During Revision Total Knee Arthroplasty Is Not Associated With Increased Risk of 30-Day Postoperative Complication.

Background: Academic teaching institutions perform approximately one third of all orthopedic procedures in the United States. Revision total knee arthroplasty (rTKA) is a complex and challenging procedure that requires expertise and extensive planning, however the impact of resident involvement on outcomes is poorly understood. The aim of the study was to investigate whether resident involvement in rTKA impacts postoperative complication rates, operative time, and length of hospital stay (LOS). Methods: The American College of Surgeons National Surgical Quality Improvement Program registry was queried to identify patients who underwent rTKA procedures from 2006-2012 using CPT codes 27486 and 27487. Cases were classified as resident involved or attending only. Demographics, comorbidities, and 30-day postoperative complications were analyzed. Multiple logistic regression analysis was performed to identify independent risk factors for increased 30-day postoperative complications. Wilcoxon rank sum tests were performed to determine the impact of resident involvement on operative time and LOS with significance defined as p<0.05. Results: In total, 2,396 cases of rTKA were identified, of which 972 (40.6%) involved residents. The two study groups were similar, however the resident involved cohort had more patients with hypertension and ASA class 3 (p=0.02, p=0.04). There was no difference in complications between the cohorts (No Resident vs Resident-involved: 7.0% vs 6.7%, p=0.80). Multivariate analysis identified obesity (OR: 1.81, 95% CI: 1.18-2.79, p=0.01), morbid obesity (OR: 1.66, 95% CI: 1.09-2.57, p=0.02), congestive heart failure (OR: 5.97, 95% CI: 1.19-24.7, p=0.02), and chronic prosthetic joint infection (OR: 3.16, 95% CI: 2.184.56, p<0.01), as independent risk factors for 30-day complications after rTKA. However, resident involvement was not associated with complications within 30-days following rTKA (OR: 0.91, 95% CI: 0.65-1.26, p=0.57). Resident involvement was associated with increased operative time (p<0.001) and LOS (P<0.001). Conclusion: Resident involvement in rTKA cases is not associated with an increased risk of 30-day postoperative complications. However, resident operative involvement was associated with longer operative time and length of hospital stay. Level of Evidence: III.