Does Fracture Pattern Really Predict Displacement of LC1 Sacral Fractures?

BACKGROUND: Operative management of minimally displaced lateral compression type-1 (LC1) pelvic ring injuries remains controversial. We aimed to assess the proportion of LC1 pelvic fractures that displaced following nonoperative management as a function of specific ring fracture patterns, and we quantified the magnitude of this displacement. METHODS: A retrospective review of the billing registry of a level-I trauma center was performed. Two hundred and seventy-three patients with a high-energy LC1 pelvic ring fracture and <5 mm of sacral displacement were included. The fracture pattern was characterized with use of computed tomography (CT) scans and radiographs. Absolute and interval pelvic ring displacement were quantified with use of previously described methodology. RESULTS: Thirty-five pelvic ring injuries (13%) were displaced. The rate of displacement was 31% (15 of 49) for LC1 injuries involving a complete sacral fracture and bilateral ramus fractures, 12% (7 of 58) for injuries involving a complete sacral fracture and a unilateral ramus fracture, and 10% (5 of 52) for injuries involving an incomplete sacral fracture and bilateral ramus fractures. In displaced injuries, the average interval displacement was 4.2 mm (95% confidence interval [CI], 1.8 to 6.8) and the final displacement was 9.9 mm ± 4.2 mm. CONCLUSIONS: Our study suggests that fracture characteristics can be used to predict the likelihood of displacement of LC1 fractures that are treated without surgery. To our knowledge, the present study is the first to describe the magnitude of displacement that may occur in association with LC1 pelvic ring injuries that are treated nonoperatively; however, further studies are needed to determine the clinical impact of this displacement. LEVEL OF EVIDENCE: Diagnostic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Are non-invasive estimations of plasma volume an accurate measure of congestion in patients with chronic heart failure?

AIMS: We report associations between different formulae for estimating plasma volume status (PVS) and clinical and ultrasound markers of congestion in patients with chronic heart failure (CHF) enrolled in the Hull Lifelab registry. METHODS AND RESULTS: Cohort 1 comprised patients with data on signs and symptoms at initial evaluation (n = 3505). Cohort 2 included patients with ultrasound assessment of congestion [lung B-line count, inferior vena cava (IVC) diameter, jugular vein distensibility (JVD) ratio] (N = 341). Two formulae for PVS were used: (a) Hakim (HPVS) and (b) Duarte (DPVS). Results were compared with clinical and ultrasound markers of congestion. Outcomes assessed were mortality and the composite of heart failure (HF) hospitalisation and all-cause mortality. In cohort 1, HPVS was associated with mortality [hazard ratio (HR) per unitary increase = 1.02 (1.01-1.03); P < 0.001]. In cohort 2, HPVS was associated with B-line count (HR) = 1.05 [95% confidence interval (CI) (1.01-1.08); P = 0.02] and DPVS with the composite outcome [HR = 1.26 (1.01-1.58); P = 0.04]. HPVS and DPVS were strongly related to haemoglobin concentration and HPVS to weight. After multivariable analysis, there were no strong or consistent associations between PVS and measures of congestion, severity of symptoms, or outcome. By contrast, log[NTproBNP] was strongly associated with all three. CONCLUSION: Amongst patients with CHF, HPVS and DPVS are not strongly or consistently associated with clinical or ultrasound evidence of congestion, nor clinical outcomes after multivariable adjustment. They appear only to be surrogates of the variables from which they are calculated with no intrinsic clinical utility.

Effects of Delayed Hip Fracture Surgery on Severely Ill Patients: Defining the Time to Medical Optimization.

BACKGROUND: Patients with multiple comorbidities often have delayed hip fracture surgery due to medical optimization. The goal of this study is to identify the allowable time for medical optimization in severely ill hip fracture patients. METHODS: The 2016-2019 NSQIP database was used to identify patients over age 60 with ASA classification scores 3 and 4 for severe and life-threatening systemic diseases. Patients were divided into immediate (<24 hours), early (24-48 hours), or late (>48 hours) groups based on time to surgery (TTS). Risk-adjusted multivariable logistic regressions were conducted to compare relationships between 30-day postoperative outcomes and TTS. RESULTS: 43,071 hip fracture cases were analyzed for the purposes of this study. Compared to patients who underwent surgery immediately, patients who had surgeries between 24 and 48 hours were associated with higher rates of pneumonia (OR 1.357, CI 1.194-1.542), UTIs (OR 1.155, CI 1.000-1.224), readmission (OR 1.136, CI 1.041-1.240), postoperative LOS beyond 6 days (OR 1.249, CI 1.165-1.340), and mortality (OR 1.205, CI 1.084-1.338). Patients with surgeries delayed beyond 48 hours were associated with higher rates of CVA (OR 1.542, CI 1.048-2.269), pneumonia (OR 1.886, CI 1.611-2.209), UTIs (OR 1.546, CI 1.283-1.861), readmission (OR 1.212, CI 1.074-1.366), postoperative LOS beyond 6 days (OR 1.829, CI 1.670-2.003), and mortality (OR 1.475, CI 1.286-1.693) compared to patients with immediate surgery. DISCUSSION: Severely ill patients with the hip fracture may have a 24-hour window for medical optimization. Hip fracture surgery performed beyond 48 hours is associated with higher complication rates and mortality among those who are severely ill. Further prospective studies are warranted to examine the effects of early surgical intervention among severely ill patients.

Heterotopic Ossification Prophylaxis in Acetabular Fracture Surgery: A Systematic Review.

Heterotopic ossification (HO) following acetabular fracture surgery is relatively common. The purpose of this study was to perform a systematic review of the literature regarding HO rates following acetabular surgery and the effectiveness of the various prophylactic measures taken to prevent its occurrence. A search of PubMed, MEDLINE, and Cochrane Database of Systematic Reviews was performed using the search terms ("Acetabular" OR "Acetabulum") AND ("Heterotopic Ossification" OR "HO" OR "Ectopic Ossification"). Inclusion criteria included articles published in English reporting on HO in acetabular fracture surgery. Descriptive statistics were calculated with categorical data presented as frequency with percentages and continuous data as means. Standard weighted means were calculated for all parameters. Sixty-six articles were included in this study with a total of 5,028 patients. HO was identified in 1,511 (30%) of fractures. Indomethacin (27%) and radiation therapy (24%) demonstrated decreased rates of HO formation versus no prophylaxis (36%). In particular, rates of severe HO formation were substantially decreased with radiation therapy (3%) and indomethacin (7%) compared to no prophylaxis (18%). Indomethacin and radiation therapy both appear to decrease HO formation and severity without substantially increasing surgical morbidity. (Journal of Surgical Orthopaedic Advances 32(4):217-224, 2023).

Outcomes of Iliac Wing Fractures: A Systematic Review of the Literature.

To review the literature on iliac wing fractures to assess outcomes of operative and nonoperative treatment. A search of PubMed, MEDLINE, and Cochrane Database of Systematic Reviews was performed. Articles reporting on iliac wing fractures without pelvic ring destabilization or intraarticular extension were included. Study information and patient data were collected, and a Methodological Index for Non-randomized Studies (MINORS) score was assigned to each article. In total, 19,363 articles were identified with 32 qualifying for inclusion. The articles included 131 patients with 133 fractures. The mean age was 43.6, and mean follow-up time was 41.9 months. Forty-eight (36%) fractures were treated operatively, and 85 (64%) were treated nonoperatively. Associated injuries included bowel injuries, other pelvic fractures, gunshot wounds, and arterial injuries. There is an absence of comparative studies between operative and nonoperative management of iliac wing fractures. Indications for operative management appear to depend on comminution, open fractures, and associated injuries. (Journal of Surgical Orthopaedic Advances 32(3):139-147, 2023).

A Review on Management of Insufficiency Fractures of the Pelvis and Acetabulum.

"Insufficiency fractures of the pelvis and acetabulum are occurring at increasing rates. Osteoporosis is the most prevalent risk fracture. Diagnosis begins with plain radiographs followed by advanced imaging with computed tomography and/or MRI. Pelvic ring fragility injuries are classified by the Fragility fractures of the pelvis system. Elderly acetabular fractures may be classified by the Letournel system. Management of these injuries is primarily nonoperative with early immobilization when allowed by fracture characteristics. When warranted, percutaneous fixation and open reduction internal fixation are options for both. Both acute and delayed total hip arthroplasty are options for acetabular fractures."

Risk factors for loss to follow up of pelvis and acetabular fractures.

INTRODUCTION: Pelvic and acetabular fracture incidence is increasing worldwide for more than four decades. There is currently no evidence examining risk factors for loss to follow up in patients with these injuries. METHODS: Patients presenting with pelvic and/or acetabular fractures at our institution between 2015 and 2020 were included. Demographic, injury, treatment, and follow up information was included. Excluded patients were those who sustained a pathologic fracture, has a course of treatment prior to transfer to our centre, or expired prior to discharge. RESULTS: 446 patients, 263 with a pelvic ring injury, 172 with an acetabular fracture, and 11 with combined injuries were identified. 271 (61%) of patients in our cohort followed up in Orthopaedic clinic (p = 0.016). With an odds ratio of 2.134, gunshot wound mechanism of injury was the largest risk factor for loss to follow up (p = 0.031) followed by male sex (OR= 1.859) and surgery with general trauma surgery (OR=1.841). The most protective risk factors for follow up with Orthopaedic surgery were operatively treated pelvic and acetabular fractures (OR=0.239) and Orthopaedic Surgery as the discharging service (OR=0.372). DISCUSSION: Numerous risk factors exist for loss to follow up including male sex, ballistic mechanism, and discharging service. Investigation into interventions to improve follow up in these patients are warranted.

The Effect of Surgeon Experience on Short- to Medium-Term Complication Rate Following Operative Fixation of Acetabular Fractures.

OBJECTIVES: Operative management of acetabular fractures is technically challenging, but there is little data regarding how surgeon experience affects outcomes. Previous efforts have focused only on reduction quality in a single surgeon series. We hypothesized that increasing surgeon experience would be associated with improved acetabular surgical outcomes in general. DESIGN: Retrospective cohort study. SETTING: Urban academic level-I trauma center. PATIENTS/PARTICIPANTS: Seven hundred ninety-five patients who underwent an open reduction internal fixation for an acetabular fracture. RESULTS: There was a significant association between surgeon experience and certain outcomes, specifically reoperation rate (16.9% overall), readmission rate (13.9% overall), and reduction quality. Deep infection rate (9.7% overall) and secondary displacement rate (3.7% overall) were not found to have a significant association with surgeon experience. For reoperation rate, the time until 50% peak performance was 2.4 years in practice. CONCLUSION: Surgeon experience had a significant association with reoperation rate, quality of reduction, and readmission rate after open reduction internal fixation of acetabular fractures. Other patient outcomes were not found to be associated with surgeon experience. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Orthopaedic Surgery Residency Program Websites: A Five-Year Update and the Rise of Social Media.

Objective  The importance of online information in the form of residency program websites has been well documented. With the rise of popularity of social media, another potential vital source of online information distribution exists. We aimed to examine the changes in orthopaedic surgery residency program websites and determine the use of social media by these programs. Methods A list of orthopaedic residency programs was obtained. Websites were then assessed for presence of numerous criteria. The presence of a social media account on Instagram, Twitter, and Facebook platforms was then determined. Results One hundred ninety-five websites out of 197 programs were identified. The most commonly present criterion was resident rotation schedule with 187 (96%) listings. Meanwhile, information on virtual sessions for prospective applicants was the least present at 26 (13%). Out of the 33 criteria assessed, websites contained an average of 20.4 criteria. Approximately half of the programs were noted to have a social media presence. Conclusion Website utilization and accessibility have improved over time as the importance of online information has continued to grow in the orthopaedic surgery residency application process. In order to increase their online presence, numerous programs have recently created or enhanced the profiles on social media platforms which may reach more users than websites alone.

Characteristics and Trends of Highly Cited Articles in Calcaneus Fracture Research.

Background: Despite significant effort expended toward exploring fracture patterns, surgical timing, surgical approaches, and possible implants within the calcaneus fracture literature, treatment is still fraught with complications and controversy. This study aims to conduct a citation analysis of the most cited articles related to calcaneus fractures to highlight the most historically influential articles, as well as the more recent breakthrough articles that are leading change within the field. Methods: A literature search was performed via Scopus on September 20, 2021 using the terms "(calcaneus OR calcaneal OR hindfoot) AND (fracture OR injury)" to search "article title, abstract, and keywords" of all primary and review articles. Search results were rigorously reviewed to ensure appropriateness for this study. The 50 highest total cited included articles were analyzed. Title, authors, journal, country of origin, institution, year of publication, citation variables (total citation count, total citation density, citation count from the last 5 years, and 5-year citation density), and level of evidence were collected for each article. One-way analysis of variance with post hoc testing was used to identify differences in citation variables and level of evidence. Pearson correlation was used to directly compare different citation variables. Results: The total citation count average was 178±33, with a total citation density average of 9±2. The year of publication for the 50 articles ranged from 1948 to 2014, with a median year of 1999. Roy W. Sanders was the most productive author in the field, authoring 6 articles and lead authoring 3. The most frequent level of evidence was IV with 19 articles. There was a strong correlation between total citation density and 5-year citation density. The article level of evidence showed no impact on the included measures of an article's influence. Conclusion: This study successfully analyzes and presents the characteristics among the highest cited articles related to calcaneus fractures. The provided characterization of influential works and authors highlights trends, impactful findings, and future areas of focus within calcaneus fracture literature.Level of Evidence: Review Article.

Determining the Impact of the COVID-19 Pandemic on Hand Surgery Fellowship Education.

The purpose of this study is to report the impact of COVID-19 on hand surgery fellow learning and preparedness for practice. A multi-dimensional questionnaire was distributed to current hand fellows and fellowship directors across the United States. Survey questions included fellowship location, institutional response, impact on practice, education and job search. Thirty-two hand surgery fellows and 14 fellowship directors completed the survey. Of fellows, 59% reported a greater than 75% decrease in case volume. Mean hours worked per week per fellow decreased by 52%. All fellowship directors and 94% of fellows did not expect COVID-19 to impact their ability to graduate, and nearly all fellows felt prepared to start practice after fellowship training. However, many fellows expressed concern about job opportunities. The work hours and exposure of hand surgery fellows to elective surgical cases have been adversely impacted by COVID-19. Nevertheless, current hand fellows feel prepared to enter practice. (Journal of Surgical Orthopaedic Advances 31(1):048-052, 2022).

Incidence, risk factors and clinical implications of postoperative urinary tract infection in geriatric hip fractures.

INTRODUCTION: Postoperative urinary tract infection (UTI) is common in geriatric patients; however, little is known about the impact of UTI in orthopedic trauma. The present study was designed to determine the risk factors and clinical impact of postoperative urinary tract infection (UTI) in acute geriatric hip fractures. PATIENTS AND METHODS: Geriatric patients (≥65 years of age) undergoing hip fracture surgery were identified within the American College of Surgeons National Surgical Quality Improvement Program between 2016 and 2019. Patients presenting with UTI at the time of surgery were excluded. Baseline characteristics and outcomes were compared between patients with and without postoperative UTI. Multivariate logistic regression was performed, controlling for potential confounders. RESULTS: A total of 46,263 patients included in the study. Overall, 1,397 (3.02%) patients had postoperative UTI. Patients who developed postoperative UTI had higher rates of pneumonia (6.44% vs. 3.76%, p < 0.001), DVT (2.22% vs. 1.04%, p < 0.001), sepsis (7.73% vs. 0.62%, p < 0.001), and more frequently experienced postoperative hospital lengths of stay exceeding 6 days (37.94% vs. 20.33%, p < 0.001). Hospital readmission occurred more frequently in patients with postoperative UTI (24.55% vs. 7.85%, p < 0.001), but surprisingly, these patients had a lower mortality rate (1.36% vs. 2.2%, p < 0.001). Adjusted analysis demonstrated the following variables associated with postoperative UTI: age ≥ 85 (OR = 1.37, 95%CI = 1.08 - 1.73), ASA class ≥ 3 (OR = 1.59, 95%CI = 1.21 - 2.08,), chronic steroid use (OR = 1.451, 95%CI = 1.05 - 1.89), blood transfusion (OR = 1.24, 95%CI = 1.05 - 1.48), and >2 days delay from admission to operation (OR = 1.37, 95%CI = 1.05 - 1.79). Postoperative UTI was significantly associated with sepsis (OR = 7.65, 95%CI = 5.72 - 10.21), postoperative length of stay >2 days (OR = 1.83, 95%CI = 1.07 - 3.13), and readmission (OR = 3, 95%CI = 2.54 - 3.55). CONCLUSIONS: In our study, postoperative UTI was found in 3% of geriatric hip fracture patients. Predictors of postoperative UTI were age ≥ 85, ASA class ≥ 3, chronic steroid use, blood transfusion, and time to operation > 2 days from admission. Results showed that postoperative UTI is independently associated with sepsis, postoperative length of stay beyond 2 days, and hospital readmission. To diminish the risk of UTI and its consequences, we recommend operating geriatric hip fractures in 24-48 hours after admission.

Algorithm Improves Acetabular Fracture Radiograph Interpretation Among Inexperienced Practitioners.

Acetabular fractures are often first evaluated in the emergency department, where physicians with little experience reading pelvic radiographs may be required to make an accurate diagnosis and early management decisions. In this study, medical students classified radiographs of 20 acetabular fractures and repeated the exercise three weeks later with the aid of a previously described algorithm; half the students were given a lesson prior to using the algorithm. The pre-algorithm accuracy was 4/20 and the post-algorithm accuracy was 8.3/20 (p<0.01). The lesson provided no difference (p=0.5). This algorithm is therefore a useful reference to help classify and triage acetabular fractures.

Comparison of Extramedullary and Intramedullary Implants for Stable Intertrochanteric Fractures: Have We Swung the Pendulum Too Far the Other Way?

INTRODUCTION: Although intramedullary implants are commonly used to treat stable intertrochanteric (IT) fractures, there is a lack of evidence to demonstrate their superiority over extramedullary implants in treating these fractures. The purpose of this study was to compare short-term outcomes (<30 days) between intramedullary and extramedullary implants in patients with closed nondisplaced stable IT fractures. METHODS: Patients with closed nondisplaced stable IT fractures were identified from the American College of Surgeons National Surgical Quality Improvement Program database between 2016 and 2019. Patients who either underwent extramedullary implant or intramedullary implant fixation were selected for this analysis. Postoperative outcomes included transfusion, surgical complications (stroke, myocardial infarction, venous thromboembolism, pneumonia, renal failure/insufficiency, surgical site infection, urinary tract infections, and sepsis), weight-bearing on postoperative day 1, discharge destination, place of residence at 30 days after the operation, days from operation to discharge, readmission related to the index procedure, any readmission, revision surgery, and mortality. RESULTS: Of the 3,244 cases identified for the study, 2,521 (77.7%) underwent intramedullary nailing (IMN). Based on adjusted multivariable analysis, surgical complications between the two intervention groups were not statistically significantly (odds ratio [OR] 1.142; confidence interval [CI], 0.838 to 1.558; P = 0.4). However, patients who underwent IMN were associated with higher rates of blood transfusions (OR, 1.35, CI, 1.042 to 1.748, P = 0.023), more likely discharged to a place other than home (OR, 1.372, CI, 1.106 to 1.700, P = 0.004), and more likely to get readmitted (OR, 1.783, CI, 1.157 to 2.75, P = 0.009). Patients treated with IMN were associated with lower postoperative length of stay (OR 0.982, CI 0.967 to 0.998, P = 0.030). DISCUSSION: Our study found that extramedullary implants were associated with lower transfusions rates, lower readmissions, and better patient disposition. We recommend surgeons to consider extramedullary implants when treating stable IT fractures, especially if the patient is anemic or at high risk for hospital readmission. LEVEL OF EVIDENCE: Level III. Retrospective cohort study.

The Geriatric Nutritional Risk Index Is an Independent Predictor of Adverse Outcomes for Total Joint Arthroplasty Patients.

BACKGROUND: Malnutrition affects patient outcomes after total joint arthroplasty (TJA). Although hypoalbuminemia has been used as a surrogate, there is no unanimous method for screening and assessing malnutrition. This study aimed to determine if malnutrition, as defined by the Geriatric Nutritional Risk Index (GNRI), is independently correlated with short-term (<30 days) postoperative complications and prognosis in patients undergoing TJA. METHODS: The 2016-2019 American College of Surgeons National Surgical Quality Improvement Program was queried for all patients aged >65 years who underwent TJA. Based on GNRI value, patients were divided into 3 groups: normal nutrition (GNRI >98), moderate malnutrition (GNRI 92-98), and severe malnutrition (GNRI <92). After adjusting for potential confounders, multivariable regression models were used to analyze the association between GNRI and patient outcomes. RESULTS: A total of 191,087 patients were included in the study. Prevalence of malnutrition based on body mass index (<18.5 kg/m2), albumin (<3.5 mg/dL), and GNRI (≤98) was 0.41% (784), 4.17% (7975), and 15.83% (30,258). Adjusted analysis showed that compared with normal nutrition, moderate and severe malnutrition status were associated with a higher rate of transfusion, readmission, and postoperative length of stay over 8 days (P < .05). Severe malnutrition was also associated with pneumonia, surgical site infection, urinary tract infection, sepsis, and revision surgery (P < .05). CONCLUSION: Malnutrition, as defined by GNRI, is an independent predictor of adverse outcomes after TJA, including 30-day readmission, revision surgery, and increased length of stay. GNRI can be used to routinely screen and assess patient nutritional status before TJA and counsel patients and families appropriately. LEVEL OF EVIDENCE: Level 3: Retrospective Cohort Study.

Clinical Outcomes and Surgical Complications Among Patients with Bleeding Disorders After Acute Hip Fracture Surgery.

OBJECTIVE: To compare short-term (≤30 days) outcomes of hip fracture between patients with and without bleeding disorders. DESIGN: Retrospective database review. SETTING: The study setting included hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program database. PATIENTS: Patients with acute hip fractures were identified from the National Surgical Quality Improvement Program database between 2016 and 2019. INTERVENTION: Open reduction internal fixation or hemiarthroplasty. MAIN OUTCOME MEASUREMENTS: Mortality, readmission, reoperation, length of stay, and complication were main outcome measurements. RESULTS: There were 63,718 patients undergoing hip surgery, and 16.0% had a bleeding disorder. After adjusting for confounders, multivariable regression models showed that cases with bleeding disorders were associated with higher rates of transfusion [odds ratio (OR) 1.404; confidence interval (CI), 1.335-1.479], myocardial infarction (OR 1.367; CI, 1.190-1.572), pneumonia (OR 1.193; CI, 1.078-1.321), renal failure (OR 1.843; CI, 1.363-2.491), surgical site infections (OR 1.429; CI, 1.185-1.175), sepsis (OR 1.25; CI, 1.034-1.511), and readmission (OR 1.314; CI, 1.224-1.408). However, bleeding disorders were not associated with mortality (OR 0.947; CI, 0.866-1.036) or reoperation (OR 1.061; CI, 0.925-1.220). CONCLUSIONS: Hip fracture surgery in patients with bleeding disorders is not associated with higher risks of short-term mortality or reoperation. However, special consideration should be taken when calculating preoperative risks of complications among bleeding disorder patients. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Superficial Deltoid Ligament and Deep Deltoid Ligament Play Equally Important Roles in the Stability of Isolated Lateral Malleolus (OTA/AO 44-B1) Fractures: A Biomechanical Study.

OBJECTIVE: To evaluate the individual contributions to stability of the superficial and deep deltoid ligaments in the setting of SER IV ankle fractures. METHODS: Nineteen total cadaveric specimens were used. SER IV injuries were created with the rupture of either the superficial (SER IV-S) (n = 9) or deep deltoid (SER IV-D) (n = 10). These were tested by applying an external rotation force (1 Nm, 2 Nm, 3 Nm, and 4 Nm). Changes in the position of the talus were recorded with a 3D motion tracker. Injury conditions were compared with a 4-step general linear model with repeated measures. Injury condition was also compared with the intact state and to each other using 2-tailed t tests. RESULTS: The general linear model showed that increased loading had a significant effect with axial rotation (P = 0.02) and sagittal translation (P = 0.003). SER IV-S and SER IV-D showed significantly greater instability compared with the intact state in axial rotation (1 Nm, 2 Nm, and 3 Nm). SER IV-S and SER IV-D did not significantly differ from each other. CONCLUSIONS: SER IV fracture patterns can be unstable with isolated injury to either the superficial or deep deltoid. This challenges the notion that deep deltoid rupture is necessary. Further clinical studies would help quantify the consequences of this instability.

Calcaneal Reconstruction With Femoral Head Allograft Vascularized by an Osteocutaneous Medial Femoral Condyle Flap: A Case Report.

CASE: A 25-year-old man presented with a closed calcaneal fracture after a 6-storey fall, complicated by osteomyelitis from fixation attempts necessitating near-complete debridement of his calcaneal tuberosity. He underwent a successful single-stage calcaneal and soft-tissue reconstruction using a femoral head structural allograft vascularized with an osteocutaneous medial femoral condyle flap. At the 18-month follow-up, his limb is largely pain-free and functional, allowing ambulation and his combined allograft-vascularized bone reconstruction shows radiographic evidence of incorporation. CONCLUSION: Calcaneal tuberosity reconstruction with a femoral head structural allograft and vascularized bone flap is a viable option for calcaneal tuberosity bone loss because of injury/infection.

On the generalizability of diffusion MRI signal representations across acquisition parameters, sequences and tissue types: Chronicles of the MEMENTO challenge.

Diffusion MRI (dMRI) has become an invaluable tool to assess the microstructural organization of brain tissue. Depending on the specific acquisition settings, the dMRI signal encodes specific properties of the underlying diffusion process. In the last two decades, several signal representations have been proposed to fit the dMRI signal and decode such properties. Most methods, however, are tested and developed on a limited amount of data, and their applicability to other acquisition schemes remains unknown. With this work, we aimed to shed light on the generalizability of existing dMRI signal representations to different diffusion encoding parameters and brain tissue types. To this end, we organized a community challenge - named MEMENTO, making available the same datasets for fair comparisons across algorithms and techniques. We considered two state-of-the-art diffusion datasets, including single-diffusion-encoding (SDE) spin-echo data from a human brain with over 3820 unique diffusion weightings (the MASSIVE dataset), and double (oscillating) diffusion encoding data (DDE/DODE) of a mouse brain including over 2520 unique data points. A subset of the data sampled in 5 different voxels was openly distributed, and the challenge participants were asked to predict the remaining part of the data. After one year, eight participant teams submitted a total of 80 signal fits. For each submission, we evaluated the mean squared error, the variance of the prediction error and the Bayesian information criteria. The received submissions predicted either multi-shell SDE data (37%) or DODE data (22%), followed by cartesian SDE data (19%) and DDE (18%). Most submissions predicted the signals measured with SDE remarkably well, with the exception of low and very strong diffusion weightings. The prediction of DDE and DODE data seemed more challenging, likely because none of the submissions explicitly accounted for diffusion time and frequency. Next to the choice of the model, decisions on fit procedure and hyperparameters play a major role in the prediction performance, highlighting the importance of optimizing and reporting such choices. This work is a community effort to highlight strength and limitations of the field at representing dMRI acquired with trending encoding schemes, gaining insights into how different models generalize to different tissue types and fiber configurations over a large range of diffusion encodings.

Techniques for predicting and avoiding unintentional biplanar movements during iliosacral screw placement.

The technique for placing iliosacral screws typically involves the surgeon using an inlet and outlet view as the primary means for assessing the anteroposterior and craniocaudal position of the guidewire, respectively. However, because these views are rarely, if ever, orthogonal to one another, this technique will inevitably lead to unintentional biplanar movements. These unintentional movements, in turn, require correction, which can increase operating room and fluoroscopic time. Here we calculate the degree and magnitude of these unintentional movements. Additionally, we provide a simple technique for minimizing or eliminating them altogether.