Introduction and An Analysis of Inter- and Intra-observer Validity to the Classification of Hoffa-Like Tibial Plateau Fractures.

OBJECTIVE: The posterior coronal shearing fractures of the tibial plateau are rare and can be easily missed or ignored. Our team defined these fractures as Hoffa-like fracture of the tibial plateau and conducted a series of studies. The aim of this study is to introduce the characteristics of the Hoffa-like fracture of the tibial plateau, propose a new classification system and evaluate its validity. METHODS: Sixty-one patients with Hoffa-like fractures of the tibial plateau were treated in five trauma centers (I-III) from 2017 to 2020. A new classification system was developed based on the morphological fracture patterns in CT and radiographic of the first 30 cases. Ten cases of suspected tibial plateau Hoffa-like fractures were supplemented additionally to the 61 cases to increase the accuracy. CT and radiographic images of the 71 cases were reviewed independently by four reviewers on two separate occasions and classified according to the new classification system. Cohen's kappa coefficient (κ) was used to analyze the reliability on separate observers at the same time and to analyze the classification made by same observer at different times (intra-observer), which measures inter-observer and intra-observer agreements. RESULTS: Out of the 61 patients, 46 (75.4%) isolated coronal fractures involving the medial condyle of tibial plateaus and 53 (86.9%) combined with intercondylar spine fractures. The κ-values were calculated for the new classification system (mean κ = 0.74 inter-observer, mean κ = 0.79 intra-observer, indicating substantial agreement). CONCLUSION: The novel classification lends insight into fracture morphology of the tibial plateau Hoffa-like fractures, has good inter- and intra-observer validity, and it aids in treatment.

Development and validation of a deep learning-based model to distinguish acetabular fractures on pelvic anteroposterior radiographs.

Objective: To develop and test a deep learning (DL) model to distinguish acetabular fractures (AFs) on pelvic anteroposterior radiographs (PARs) and compare its performance to that of clinicians. Materials and methods: A total of 1,120 patients from a big level-I trauma center were enrolled and allocated at a 3:1 ratio for the DL model's development and internal test. Another 86 patients from two independent hospitals were collected for external validation. A DL model for identifying AFs was constructed based on DenseNet. AFs were classified into types A, B, and C according to the three-column classification theory. Ten clinicians were recruited for AF detection. A potential misdiagnosed case (PMC) was defined based on clinicians' detection results. The detection performance of the clinicians and DL model were evaluated and compared. The detection performance of different subtypes using DL was assessed using the area under the receiver operating characteristic curve (AUC). Results: The means of 10 clinicians' sensitivity, specificity, and accuracy to identify AFs were 0.750/0.735, 0.909/0.909, and 0.829/0.822, in the internal test/external validation set, respectively. The sensitivity, specificity, and accuracy of the DL detection model were 0.926/0.872, 0.978/0.988, and 0.952/0.930, respectively. The DL model identified type A fractures with an AUC of 0.963 [95% confidence interval (CI): 0.927-0.985]/0.950 (95% CI: 0.867-0.989); type B fractures with an AUC of 0.991 (95% CI: 0.967-0.999)/0.989 (95% CI: 0.930-1.000); and type C fractures with an AUC of 1.000 (95% CI: 0.975-1.000)/1.000 (95% CI: 0.897-1.000) in the test/validation set. The DL model correctly recognized 56.5% (26/46) of PMCs. Conclusion: A DL model for distinguishing AFs on PARs is feasible. In this study, the DL model achieved a diagnostic performance comparable to or even superior to that of clinicians.

Displacement Pattern of Anterior and Posterior Column Fragments in Both-Column Acetabular Fractures: A 3D Reconstruction-Based Study.

Background: Few studies have been conducted to examine the displacement characteristics of both-column acetabular fractures (BCAFs). The goal of this study was to investigate the displacement pattern of anterior column (AC) and posterior column (PC) fragments in BCAFs using 3D virtual software. Materials and Methods: BCAFs were retrospectively reviewed, and 81 patients were enrolled. Computed tomography (CT) images were imported into Mimics software. A 3D model of each pelvis was generated. Four marked points and the rotation angle of each of the injured ACs and PCs were identified. The fracture fragments were reduced virtually using the software, and the change in coordinates of the marked points after reduction was recorded while the rotation angle was measured. The measurements of positional and directional displacement were analysed using the Mann-Whitney U test and the binomial test, respectively. Results: There was a propensity for AC fragments to shift superomedially and to rotate externally (p < 0.001). Additionally, the posteroinferior fracture area of AC fragments showed the greatest displacement (p < 0.05). PC fragments moved superomedially (p < 0.001) and moved more at the proximal end than the distal end (p < 0.001). PC displacement was always accompanied by internal rotation (p < 0.001). Greater AC displacement was observed in the fracture area further away from the acetabulum (p < 0.05). Greater rotation was observed for the AC than the PC (p < 0.001). Conclusion: After a BCAF occurs, there are regular patterns regarding the direction and distance of AC and PC fragment displacement. Information on these patterns may provide insight into the injury mechanism and fracture morphology and facilitate surgical decision-making for orthopaedic trauma surgeons.

Is the T-shaped acetabular fracture really likes a "T"? A study based on three-dimensional fracture mapping.

OBJECTIVES: To explore the morphological pattern of T-shaped acetabular fractures (T-SAFs) by mapping the fracture line using 3D software. MATERIAL AND METHODS: We retrospectively reviewed 1298 consecutive patients with acetabular fractures, and a total of 56 T-SAF patients were enrolled. After the simulated reduction of each fracture in the software, the fracture lines of all patients were overlaid and plotted on a template. A frequency heat map was generated according to the differences in fracture line density distribution. According to the location of fracture lines, all cases were divided into three groups: posterior group, anterior group, extra-posterior group. In surgically treated patients, the surgical approach, fixation methods, and reduction quality were recorded or evaluated. RESULTS: The transverse fracture line was sinuous without involving the acetabular roof, and the longitudinal fracture line sloped forward or backward along the edge of the acetabular fossa to split the obturator foramen. The anterior and posterior edges of the acetabular fossa, the transition zone of the acetabular roof and anterior wall, the transition zone of the superior pubic ramus and anterior wall, and the posterior wall near the greater sciatic notch were areas with high rates of fracture incidence. The posterior group included 26 patients (46.4%) and the distribution of fracture lines resembled a "T" or "Y". The anterior group included 25 patients (44.6%) and the distribution of fracture lines resembled a "7″. The extra-posterior group included 5 patients (8.9%) and the fracture lines run through the ischial body. The surgical strategies vary among different groups of T-SAF patients. CONCLUSION: Our findings shed light on the characteristics of fracture lines for T-SAFs and provide a reference for surgical treatment strategies.

Treatment of tibial plateau fractures: A comparison of two different operation strategies with medium-term follow up.

Background: The objective of this study was to compare the clinical and radiological outcomes of two surgical methods for tibial plateau fractures (TPFs): minimally invasive surgery (MIS) using a double reverse traction repositor and traditional open reduction internal fixation (ORIF). Methods: From our prospectively collated database, 187 consecutive adult patients with 189 operatively treated TPFs in our level I trauma center were included from January 2015 to March 2018 who had a minimum of three years' follow-up. All cases were performed by the senior surgeon using either MIS (group 1, 84 patients with 84 TPFs) or ORIF (group 2, 103 patients with 105 TPFs). Details of the demographics, injury mechanism, pre- and postoperative follow-up imaging, operative procedures and complications were collected. The final results from the 36-Item Short-Form Health Survey (SF-36), Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) and Hospital for Special Surgery (HSS) were obtained at the final follow-up. Results: Clinically, significant differences were observed in the WOMAC (pain, P â€‹= â€‹0.001; stiffness, P â€‹< â€‹0.001), HSS (P â€‹= â€‹0.003) and SF-36 (P â€‹= â€‹0.001). Radiologically, significant intergroup differences were observed in the loss of immediate postoperative reduction rates, secondary loss of reduction rates and signs of osteoarthritis (Kellgren-Lawrence). Two and ten superficial infections in group 1 (2.4%) and group 2 (9.5%), respectively, and 6 lateral popliteal nerve palsy cases occurred (0 MIS, 6 ORIF), with significant intergroup differences. Conclusion: Our study shows that the MIS using a double reverse traction repositor is promising and safe technique for the TPFs when used for the correct indications. The translational potential of this article: The current status of using a minimally invasive surgery for the treatment of TPFs have been analyzed and a new method of using a double reverse traction repositor for the treatment of TPFs have been proposed in this study, which updated treatment concept of TPFs.

Morphological Characteristics of the Posterior Wall Associated with Complex Acetabular Fractures: A Radiological Study Using 3D Software and Fracture Mapping Technique.

Background: The aim of the study was to compare the morphological distinctions of the posterior wall (PW) in different complex acetabular fractures using 3D software and fracture mapping technique and ultimately to provide for improved clinical treatment. Methods: One hundred and fourteen patients with complex acetabular fracture associated with PW were recruited. All patients were divided into two groups according to the injury mechanism of the PW: Group A (both-column and PW) and Group B (including posterior column and PW; T shape and PW; and transverse and PW). Fracture mapping was generated on the intra- and extrasurface of a standard template. The radiological parameters including spatial displacement, articular surface area, articular range, marginal impaction, and multifragments of the two groups were compared. Results: The spatial displacement, intra-/extra-articular surface area, and start and end point in Group A were 10.9 mm (IQR, 8.4-15.2), 8.2 ± 2.6 cm2, 17.9 ± 5.3 cm2, 0.8° (IQR, -6.0-16.2), and 107.5° (IQR, 97.2-116.9), respectively. The results in Group B were 30.4 mm (IQR, 16.8-48.7), 4.1 ± 2.0 cm2, 10.6 ± 4.4 cm2, 29.5° (IQR, 19.2-38.0), and 117.5° (IQR, 98.2-127.2), respectively. Marginal impaction was defined by Letournel et al. All the differences between two groups were significant (P < 0.05). The fracture map in Group A showed an "L"-shaped pattern and a "cusp" on the ilium, and the PW was located at 1/5 to 1/4 of the posterosuperior part of the acetabulum. The fracture maps in Group B were scattered and lacked consistency, and the PWs were confined to 1/10 to 1/8 of the posterior acetabulum. Conclusions: Quantitative measurements and fracture mapping represented the differences in morphological characteristics of PWs associated with complex acetabular fractures.

Differences in fixation to young and elderly quadrilateral surfaces with anatomic quadrilateral surface plate (AQSP) based on cortical thickness morphological results.

AIMS: With relatively thinner cortical thickness, the management of acetabulum osteoporotic fractures in elderly patients is difficult. The aim of the research was to compare and present the morphological characteristics of the quadrilateral plate in young and elderly age groups, such as the area, and position distribution of the thin cortical thickness region, fracture lines maps, and propose a revised design plate for elderly patients based on these anatomic information. METHODS: As a retrospective research, acetabular fracture with one normal hemipelvises, including 110 men and 39 women, were collected to present the morphological characteristics of the quadrilateral region. The subjects were divided into three different age groups: Group I = 18-40 years (31.3 ± 6.6 years), Group II = 41-60 years (49.9 ± 5.3 years), and Group III ≥ 61 years (68.7 ± 6.8 years). The area of the quadrilateral surface, the area and position distribution of the thin cortical thickness region, the ratio and fracture lines maps were calculated and compared with Mimics in different groups. RESULTS: The thin cortical thickness/width region area (TCWRA) was significantly increased in Group III compared with Group I and Group II. The ratio of TCWRA accounted for in the quadrilateral region was also significantly increased in Group III (≥ 61 years) compared with Group I (P = 0.01) and Group II (P = 0.011). None of the subjects had a component involving the "A" zone, thirty-three thin cortical thickness regions were located in the "B" zone, and one hundred and sixteen involved both zones of the quadrilateral plate ("A + B" zone). Furthermore, there were a significant differences in the fracture line distributions in three age groups. More fracture lines of elderly patients were located at anterior part (B zone) compared with Group I and Group II. CONCLUSIONS: It was identified the area of thin cortical thickness region increased as age grown, and fracture lines were inclined to be more distributed in "B" zone in elderly patients. To meet the demands of acetabular fixation in different age groups, cortical thickness changes in young and elderly individuals should be given special attention when the quadrilateral surface plate is designed. Level of evidence Level IV, observational study.

Is There a "Weekend Effect" in Intertrochanteric Fracture Surgery?

INTRODUCTION: Numerous studies reported poorer outcomes for patients who were admitted at weekends or off-hour, which relates to the underlying concept called the "weekend effect." We aimed to assess the effect of adverse outcomes in older patients with intertrochanteric fracture surgery. METHODS: A retrospective cohort study of patients aged ≥65 years with intertrochanteric fracture surgery. Data were collected from computerized medical records and all patients had a long-term follow-up. The association between weekend effect with adverse outcomes and factors for all-cause mortality was studied by 3-group comparison, Spearman and partial correlation analysis, univariate analysis, and multivariate Cox proportional-hazard model. RESULTS: Our results showed no evidence supporting the existence of a weekend effect on adverse outcomes, including mortality rates (p = 0.950, log-rank), length of hospital stay, total hospital costs, rate and volume of transfusion, visual analog scale score, Harris Hip Score, and specific complications (all p > 0.05), except for an average of 0.5 days longer surgical delay found in patients admitted on Fridays relative to other days (p = 0.013). Instead, only age group (with a 10-year interval, HR 1.43, 1.28-1.59 95% CI, p < 0.001) and surgical delay (HR 1.05, 1.02-1.07 95% CI, p < 0.001) were identified as significantly associated with all-cause mortality. CONCLUSIONS: Older patients with intertrochanteric fracture surgery have similar mortality and adverse outcomes rates when admitted on weekends or holidays compared with weekdays. Our findings suggest that collaborative multidisciplinary team care seems both effective and efficient in the management of older patients with intertrochanteric fractures on any day of the week.