Posterolateral Tibial Plateau Fractures Research Articles

Incidence and Characteristics of Knee Ligament and Meniscal Injuries in Patients With Posterolateral Tibial Plateau Fractures.

Anterior cruciate ligament (ACL) tears are commonly seen with concomitant injuries to the posterolateral tibial plateau, while the occurrence of ACL injuries in posterolateral tibial plateau fractures (PTPFs) remains unclear. To (1) explore the incidence of knee ligament (anterior or posterior cruciate ligament, medial or lateral collateral ligament) and medial or lateral meniscus injuries in patients with PTPF and (2) find reliable PTPF-related parameters to predict the risk of knee ligament and meniscal injuries. Cross-sectional study; Level of evidence, 3. Patients diagnosed with PTPF who had computed tomography and magnetic resonance imaging (MRI) data were identified. Morphological parameters of the PTPF were measured on sagittal computed tomography images. Knee ligament and meniscal injuries were assessed using MRI. The association of ACL injuries with meniscal injuries was analyzed. Receiver operating characteristic (ROC) analysis was used to determine the value and cutoff point of the PTPF morphological parameters for diagnosing complete in-substance ACL tears. Overall, 113 patients with PTPF were included. ACL injuries were present in 94 (83.2%) patients, including 43 (38.1%) avulsion fractures and 28 (24.8%) complete in-substance tears. Patients with in-substance ACL tears had a higher incidence of lateral meniscus posterior horn tears compared with the other patients (PBonferroni < .001). ROC analysis revealed that both the fracture depression angle (cutoff point, 25.5°) and the posterior articular surface loss percentage (cutoff point, 37.5%) had a sensitivity >90% and a specificity >80% for the diagnosis of complete in-substance ACL tears. ACL injuries were seen in 83.2% of the study patients. Complete in-substance ACL tears were associated with an increased incidence of lateral meniscus posterior horn tears. Among PTPF parameters, fracture depression angle and posterior articular surface loss percentage showed a high predictive value for the presence of complete in-substance ACL tears, thereby reducing delays in diagnosis and treatment.

Newly designed plate for the treatment of posterolateral tibial plateau fractures: a finite element analysis

BackgroundThis study investigated the biomechanical properties of a new plate used for the treatment of posterolateral tibial plateau fractures using finite element analysis.MethodsThe study groups were as follows: group PM, model of the new plate with posteromedial tibial plateau fracture; group PL, model of the new plate with posterolateral tibial plateau fracture; and group PC, model of the new plate with posterior tibial plateau fracture. We used two loading modes: uniform loading on the entire plateau, and loading on the posterior plateau. Data such as the displacement of the fracture and distribution of stress on the new plate and screws were recorded and analyzed.ResultsWhen the whole plateau was loaded, the displacement of fractures in groups PM, PL, and PC were 0.273, 0.114, and 0.265 mm, respectively. The maximum stresses on the plates in groups PM, PL, and PC were 118.131 MPa, 44.191 MPa, and 115.433 MPa. The maximum stresses on the screws in Groups PM, PL, and PC were 166.731, 80.330, and 164.439 MPa, respectively. When the posterior tibial plateau was loaded, the displacement of the fractures in groups PM, PL, and PC was 0.410, 0.213, and 0.390 mm, respectively. The maximum stresses on the plates in groups PM, PL, and PC were 194.012 MPa, 72.806 MPa, and 185.535 MPa. The maximum stresses on the screws in Groups PM, PL, and PC were 278.265, 114.839, and 266.396 MPa, respectively.ConclusionThe results of this study revealed that titanium plates have good fixation effects in all groups; therefore, the use of the new plate for posterolateral tibial plateau fractures appears to be safe and valid.

Intra- and interobserver reliability of two classification systems for posterolateral tibial plateau fractures in the setting of an ACL rupture

BackgroundPosterolateral tibial plateau impaction fractures occur frequently associated with anterior cruciate ligament (ACL) tears. Some authors advocate operative treatment of high-grade impaction fractures, which has led to the development of classification systems. Our study aims (1) to describe and compare the intra- and interobserver reliability of the two most used classifications and (2) to assess correlations between the grade of bony posterolateral tibial injury, patient characteristics and short-to mid-term revision rate after ACL reconstruction. Materials and methodsIn a retrospective series of 163 patients who underwent ACL reconstruction, two reviewers independently evaluated the preoperative MRI scans. Conform the Menzdorf and Bernholt classification the presence and grade of an associated posterolateral impaction fracture were assessed. Statistical analyses were performed to test for both study hypotheses. Results171 primary ACL cases were evaluated. Mean follow-up time was 41 months (range 12–154, SD = 17.1). Mean age was 32 years (range 13–59, SD = 12). Posterolateral impaction fractures were present in 111 (64.9 %) and 120 (70.0 %) cases, according to the Menzdorf and Bernholt classification. A Segond fracture was present in 19 (11.1 %) cases. Kappa value was 0.47 for intra- and 0.52 for the interobserver reliability for the Menzdorf classification (moderate reliability). For the Bernholt classification kappa values were 0.66 and 0.61, respectively (good reliability). A Segond fracture correlated significantly with the presence of a posterolateral impaction fracture (p < 0.05). A significant association was present between patients necessitating ACL revision surgery and patients for whom operative intervention for the posterolateral impression was advised following the Menzdorf classification (p < 0.001). ConclusionInter- and intraobserver reliability testing for classifying posterolateral tibial fractures resulted in moderate to good reliability. High-grade posterolateral tibial fractures should be identified, selective treatment should be considered as they are associated with higher revision rates after ACL reconstruction if left untreated.

Potential problem and solution of lateral plate postposition for the posterolateral tibial plateau fracture

BackgroundThere has been controversial for the treatment of the posterolateral tibial plateau fractures (PTPF). This study aimed to evaluate clinic outcomes of the lateral locking compression plate (LCP) postposition, analyze the feasibility of LCP postposition through anatomical measurement, and address the potential problems of LCP postposition through the biomechanical assessment.Methods39 patients with PTPF undergoing LCP fixation between June 2019 and June 2022 were retrospectively evaluated. All cases were divided into two group: Group A (15 cases) employed plate transverse arm postpositioning with posterolateral (PL) fracture fixation using two raft screws, while Group B (24 cases) utilized non-postpositioning with fixation by a single raft screw. Surgical duration, intraoperative blood loss, the change of lateral tibial plateau angle (LTPA), lateral tibial plateau posterior slope angle (LPSA) and fracture collapse between immediate postoperative and last follow up, range of motion (ROM), HSS knee score, and Lysholm knee score were recorded. CT measurements of the fibular head superior space and LCP transverse arm were taken in 50 healthy adult knees to assess postposition feasibility. Finally, three fracture models were established using finite element analysis: Model A with plate postposition and PL split fracture fixed by two raft screws of transverse arm, Model B with plate non-postposition and PL split fracture fixed by one raft screw, and Model C with plate non-postposition and PL split fracture fixed by one raft screw and anterior–posterior tension screws. Loadings of 250N, 500N, and 750N were applied for the analysis of the displacement degree, von Mises stress distribution.ResultsResults indicate comparable operative duration and intraoperative hemorrhage between groups. Complications were minimal in both groups. Group A demonstrated superior outcomes in terms of radiographic parameters, functional scores, and fracture collapse prevention. CT measurements revealed compatibility in 72% of healthy knees with the postpositioning technique. Finite element analysis indicated favorable biomechanical stability.ConclusionNot all patients with PTPF were applicable to the management of the plate postposition and two raft screws fixation, even though this technique exerted good biomechanical stability and achieved satisfactory clinic outcomes. When the PL fracture was fixed by only raft screw through LCP owing to various reasons, two anterior–posterior tension screws might be necessitated to maintain the fracture stability.

A feasibility study of robot-assisted percutaneous reduction and fixation technique for treating posterolateral depression tibial plateau fractures

Posterolateral (PL)-depression fractures of the tibial plateau are difficult to manage. The aim of this study was: (1) to present our experience with a novel technique of robot-assisted percutaneous reduction and fixation and (2) to compare it with the traditional percutaneous screw osteosynthesis (PSO) technique for the treatment of PL-depression tibial plateau fractures. The clinical data of patients with PL-depression tibial plateau fractures treated by robot-assisted percutaneous reduction and fixation technique and traditional PSO technique from January 2017 to January 2021 were retrospectively analyzed. Among them, there were 18 cases in the robot-assisted group (RA group) and 23 cases in the PSO group. All fractures were unilateral, closed and fresh PL-depression fractures of the tibial plateau. Patients in the RA group were treated by robot assisted reduction and minimally invasive absorbable screw fixation. The PSO group was treated by closed reduction and percutaneous absorbable screw osteosynthesis. The incision length, operation time, intraoperative blood loss, fluoroscopic times, inpatient time, weight training time and postoperative complications of the two groups were statistically analyzed. The Rasmussen radiological score was used to assess the reduction quality after operation while the Rasmussen functional score was used to evaluate knee joint functions at one year postoperatively. All patients were followed for at least one year. There was no significant difference in demographic information between the two groups (p > 0.05). Compared with the PSO group, the RA group showed less fluoroscopic times and better Rasmussen radiological and functional scores (p < 0.05). Besides, there was no significant difference in the incidence of postoperative complications between the two groups (p > 0.05). The novel robot-assisted percutaneous reduction and fixation technique had the characteristics of less radiation, accurate reduction and fixation. It could accelerate the rehabilitation of patients with PL-depression fractures of the tibial plateau and enable patients to obtain good joint functions.

Biomechanics and finite element analysis comparing posterior T-plates with LCP for fixation of posterolateral tibial plate fractures.

Objective: The treatment for posterolateral tibial plateau fractures (PTPF) have been subjects of controversy. We conducted a study to improve the fixation of PTPF through a lateral approach. Methods: We utilized 40 synthetic tibias and categorized the fracture models into five groups based on the locking compression plate (LCP) and T-distal radius plate (TPP) via various forms of fixation with screws through the posterolateral (PL) fracture fragments. I: Two-screw fixation using two locking screws (LPTL). Ⅱ: Two-screw fixation with both variable angle locking screws (LPTV). Ⅲ: One-screw fixation with one locking screw (LPOL). Ⅳ: One-screw fixation with one locking screw and two anteroposterior lag screws (LPOLTL). Ⅴ: a distal radius plate with three locking screws (TPP). Biomechanical tests were conducted to observe the axial compression displacement of the PL fracture fragments at force levels of 250N, 500N, and 750N, as well as to determine the failure load and the axial stiffness for each respective group. Results: Under a 750N load condition, the displacements within the five experimental groups exhibited the following trend: Ⅴ < Ⅱ < Ⅰ< Ⅳ < Ⅲ. However, there were no significant differences between Group V and Group II, Group I and Group IV (p > 0.05), and only Group Ⅲ demonstrated a displacement exceeding 3mm. The failure load and the axial stiffness exhibited the same trend. Conversely, statistical significance was identified among the remaining group compared with Group Ⅲ (p < 0.05). Regarding the finite element analysis, the maximum displacements for the five models under the load of 750N exhibited the following trend: Ⅴ < Ⅱ < Ⅰ< Ⅳ < Ⅲ. The following trends were observed in maximum von Mises stresses for these models under the load of 750N: Ⅴ < Ⅱ < Ⅳ< Ⅰ < Ⅲ. Conclusion: It is crucial to address the inadequate mechanical strength associated with single screw fixation of LCP for fixing PL fractures in a clinical setting. The biomechanical strength of two-screw fixation surpasses that of single-screw fixation. Introducing variable-angle screws can further enhance the fixation range. Furthermore, the addition of two lag screws threaded from anterior to posterior can compensate the mechanical stability, when PL fracture is fixed with single screw in clinic.

Biomechanics and finite element analysis of a novel plate designed for posterolateral tibial plateau fractures via the anterolateral approach

Surgical management of posterolateral tibial plateau (PLTP) fractures is challenging. One reason for this challenge is the lack of suitable internal fixation devices. Our aim was to introduce a novel plate via the anterolateral approach for managing PLTP fractures. The biomechanical testing and finite element analysis (FEA) were performed. PLTP fracture models were created using synthetic tibias (n = 10 within each group). These models were randomly assigned to three groups (groups A-C) and fixed with the lateral locking plate, the posterior buttress plate, and the novel plate, respectively. The vertical displacement of the posterolateral fragments was evaluated using biomechanical testing and FEA under axial loads of 250 N, 500 N, and 750 N. We also evaluated the stress distribution and maximum stress of each fracture model using FEA. Biomechanically, under the same loads of 250 N, 500 N, or 750 N, the vertical displacement was significantly different among the three fixation groups (p ≤ 0.001). FEA data indicated that the maximum displacement from group A to C was 3.58 mm, 3.23 mm, and 2.78 mm at 750 N, respectively. The maximum stress from group A to C was 220.88 MPa, 194.63 MPa, and 156.77 MPa in implants, and 62.02 MPa, 77.71 MPa, and 54.15 MPa in bones at 750 N, respectively. The general trends at 250 N and 500 N were consistent with those at 750 N. Based on our biomechanical and FEA results, the novel plate could be a good option for treating PLTP fractures. The novel plate showed stable and reliable features, indicating its suitability for further clinical application.

Revisiting the flexion-valgus type unicondylar posterolateral tibial plateau depression fracture pattern: classification and treatment

ObjectiveThis study aimed to reclassify posterolateral tibial plateau fractures caused by a flexion-valgus force and describe this fracture pattern to provide a relatively programmed surgical treatment based on morphological characteristics that may improve reduction and stabilization.MethodsWe retrospectively reviewed the fracture pattern and injury mechanism of patients with posterolateral tibial plateau fractures who underwent surgery at the First Affiliated Hospital of Nanjing Medical University between January 2014 and April 2020. The cohort was divided into three types. Type I was a depression fracture of the posterolateral platform with an intact posterolateral cortex. Type II was a depression fracture of the posterolateral platform with a disrupted posterolateral cortex. Type III was a depression fracture of the posterolateral platform in combination with anterior cruciate ligament (ACL) rupture or tibial insertion avulsion fracture of the ACL. The lateral window of the modified Frosch approach with an L-type locking plate was used for patients with type I and type III fractures. For patients with type II fractures, both lateral and posterolateral windows of the modified Frosch approach were used for surgery, and a T-plate on the posterior side with an L-plate on the lateral side were used for fixation. The Rasmussen radiology scoring was used to evaluate the quality of surgical reduction and the Rasmussen functional scoring evaluation standard was used to evaluate knee joint function.ResultsA total of 69 tibial plateau fractures (36 male, 33 female) involving the posterolateral platform were discovered and included in this study. All patients suffered flexion-valgus force at the moment of the accident. There were 32 cases of Type I fracture, 28 cases of Type II fracture, and 9 cases of Type III fracture. The patients were followed up for 12–30 (mean 20.8 ± 9.4) months. The postoperative Rasmussen radiological scores for the three types of fractures were 15–17 (mean 16.31 ± 0.78), 14–17 (mean 15.93 ± 0.94), and 14–17 (mean 16.22 ± 0.97), respectively. The postoperative Rasmussen functional scores for the three types of fractions were 27–30 (mean 27.97 ± 0.90), 27–29 (mean 27.36 ± 0.56), and 27–29 (mean 27.56 ± 0.73), respectively.ConclusionFlexion-valgus posterolateral tibial plateau fractures were divided into three types based on the integrity of the posterolateral wall and ACL injuries. We hope the classification can play a certain reference role in recognizing and treating flexion-valgus-type posterolateral tibial plateau fractures.

Arthroscopic-assisted Treatment of a Posterolateral Tibial Plateau Fracture with an Accompanying Tibial Eminence Fracture. Case Report

Posterolateral tibial plateau fractures pose a challenge even to the most experienced orthopedic trauma specialists. Arthroscopic fracture management techniques have been emerging as an increasingly popular alternative in the treatment of selected tibial plateau fractures. This technique enables precise visualization of the articular surface of the tibia and its anatomical reduction with lateral meniscus repair, which further enables the restoration of biomechanical function of the meniscus and prevents early degeneration. In addition, this method minimizes soft tissue injury, shortens the duration of hospital stay and postoperative care, and enables treatment of accompanying intra-articular injuries. In our article, we present a case of posterolateral tibial plateau fracture with articular displacement and depression, and loss of support for the posterior margin of the lateral meniscus with an accompanying tibial eminence fracture. The fracture was treated with arthroscopic assistance. Anatomical reduction of the tibial eminence and the fragment of the posterolateral tibial plateau, as well as lateral meniscus repair was achieved intraoperatively. Postoperative radiographic assessment showed anatomical restoration of the articular surface. A full range of motion and pain-free knee stability were achieved following rehabilitation.

3D printing combined with anteroposterior cannulated screws for the treatment of posterolateral tibial plateau fracture

PurposeThis study aimed to compare the effects of conventional surgery and three-dimension (3D) printing technology-assisted surgery in the treatment of posterolateral tibial plateau fractures (PTPF).MethodsA cohort of 61 patients afflicted with PTPF, spanning from June 2015 to October 2021, was enrolled. They were divided randomly into two groups: 31 cases of 3D printing group, 30 cases of conventional group. The personalized 3D-printed models were used to simulate the surgical procedures in 3D printing group. The demographic characteristics and clinical data were recorded, encompassing operation duration, intraoperative blood loss, intraoperative fluoroscopy shoots and fracture union time. The radiographic outcomes were gauged, encompassing tibiofemoral angle (FTA), tibial plateau angle (TPA), posterolateral slope angle (PSA) and Rasmussen’s anatomical score. The functional outcomes were assessed at the 12-month postoperative juncture, encompassing range of motion, Hospital for Special Surgery (HSS) score and Rasmussen’s functional score. Furthermore, fracture complications were evaluated,, encompassing infections, traumatic osteoarthritis, and delayed union.ResultsThe 3D printing group exhibited the operation time of 95.8 ± 30.2 min, intraoperative blood loss of 101.1 ± 55.3 ml, and intraoperative fluoroscopy shoots of 6.3 ± 2.3 times, while the conventional group recorded respective values of 115.5 ± 34.0 min, 137.0 ± 49.2 ml and 9.13 ± 2.5 times. Noteworthy disparities were evident between the conventional and 3D printing groups (p < 0.05). Furthermore, in comparison to the conventional group, the 3D printing group exhibited commendable radiological and functional outcomes both immediately and 12 months post-surgery, although statistical significance was not attained. Moreover, the 3D printing group experienced a paucity of complications compared to the conventional group, although without achieving statistical significance.ConclusionThis study demonstrated the clinical feasibility of 3D printing combined with anteroposterior cannulated screws for the treatment of posterolateral tibial plateau fracture.

Clinical Analysis of the Frosch Approach in the Treatment of Posterolateral Tibial Plateau Fractures Combined with Lateral Tibial Plateau Fractures.

The treatment of posterolateral tibial plateau fractures is difficult, and providing sufficient exposure and effective fixation is a challenge. There is great controversy regarding the surgical approach for posterolateral tibial plateau fractures. The purpose of the study was to investigate the clinical effects of open reduction and internal fixation using the Frosch approach for the treatment of posterolateral tibial plateau fractures combined with lateral tibial plateau fractures. Data from 19 patients with posterolateral tibial plateau fractures combined with lateral tibial plateau fractures treated from May 2018 to January 2022 were retrospectively analyzed. There were nine men and 10 women, ranging in age from 22 to 62 years, with an average age of 45.6 years. All patients were treated using the Frosch approach. Under direct vision, the posterolateral and lateral fractures were reduced, and full bone grafting was performed. We reshaped the oblique "T" shaped plate for the distal radius and placed it on the posterolateral tibial plateau to fix the posterolateral fractures. The lateral inverted "L" shaped locking plate was placed on the lateral tibial plateau to fix the lateral tibial plateau fractures. Within 2 weeks after the operation, the patients were instructed to perform knee joint function exercises within 90°. At the last follow-up, the Rasmussen radiological criteria were used to evaluate the effectiveness of fracture reduction and fixation. And the knee joint function was evaluated using Rasmussen functional score. The operation time ranged from 100 to 180 min, with an average of 134.2 min; intraoperative blood loss ranged from 20 to 150 mL, with an average of 66.8 mL. The follow-up duration ranged from 14 to 58 months, with an average of 36.2 months. There were no complications, such as vascular or nerve injury or incision infection. Fracture healing was achieved in all patients, and the healing time ranged from 10 to 14 weeks, with an average of 11.2 weeks. During the follow-up period, there was no loosening or breakage of the internal fixation, varus or valgus deformity of the knee joint, re-collapse of the articular surface, or instability of the knee joint. At the last follow-up, the effectiveness of fracture reduction and fixation was excellent in 13 patients and good in six patients. And the knee joint function was excellent in 17 patients and good in two patients. The Frosch approach for open reduction and internal fixation in the treatment of posterolateral tibial plateau fractures combined with lateral tibial plateau fractures has a definite clinical benefit and is worthy of promotion and application.

Anterolateral approach for posterolateral tibial plateau fractures.

The posterolateral tibial plateau fracture is an uncommon intra-articular injury and mostly needed surgery. However, its surgical approach remains controversial. This manuscript describes an anterolateral approach to treat posterolateral tibial plateau fractures and evaluates the patient's functional outcomes. From June 2018 to July 2021 seventeen patients with posterolateral tibial plateau fractures were surgically treated through an anterolateral approach. The intraoperative and postoperative follow-up indicators were recorded. The reduction quality of fractures was assessed using Rasmussen radiological score, and postsurgical functional recovery was estimated using Rasmussen clinical score and Lysholm score. The mean follow-up interval was 28.71 ± 9.61 months (range 18-44). The surgery time and blood loss were 111.06 ± 15.62 min (range 85-140) and 118.12 ± 38.45 mL (range 80-250) separately. Postoperatively, the Rasmussen radiological score was 16.24 ± 2.33 (range 12-18). The average time of bone union was 14.29 ± 1.53 weeks (range 12-18). At the final follow-up, the average PTS and MPTA were 9.71 ± 2.76° (range 5-14°) and 86.82 ± 2.04° (range 84-90°) separately. A satisfactory articular reduction was achieved in 16 patients (94.1%). The final ROM was 123.29 ± 19.70° (range 60-142°). The Rasmussen clinical score and Lysholm score were 25.71 ± 5.74 (range 10-30) and 91.47 ± 6.50 (range 75-98) separately. Anterolateral approach has minimal risk of intraoperative neurovascular injuries in the popliteal fossa with satisfactory results. The hardware removal was also facilitated. This approach is feasible, safe and efficient.

Biomechanical analysis of tibial plateau posterolateral fracture fragment fixation and introduction of a lateral tibia plateau hook plate system

BackgroundFixing the posterolateral fragments of tibial plateau fractures has been challenging owing to potential neurovascular injuries and fibular head blocks. Several surgical approaches and fixation techniques have been reported, with distinct limitations. We propose a novel lateral tibia plateau hook plate system and compare its biomechanical stability with other fixation methods. MethodsTwenty-four synthetic tibia models were simulated to present posterolateral tibial plateau fractures. These models were randomly assigned to three groups. Group A models were fixed with the lateral tibia plateau hook plate system, Group B with variable-angle anterolateral locking compression plates, and Group C with direct posterior buttress plates. The models’ biomechanical stability was evaluated using static (gradually increased axial compressive loads) and fatigue (cyclically loaded from 100 to 600 N for 2000 cycles each) tests. ResultsGroups A and C models exhibited comparable axial stiffness, subsidence load, failure load, and displacement in the static test. Group A model exhibited higher subsidence and failure loads than Group B model. Groups A and C models exhibited comparable displacement at 100 N cyclic loading in the fatigue test. Group C model was more stable at higher loads. Group C model endured the highest subsidence cycle numbers, followed by Groups A and B models. ConclusionsThe lateral tibia plateau hook plate system provided similar static biomechanical stability as the direct posterior buttress plates and comparable dynamic stability under limited axial loading. This system is a potential posterolateral treatment choice owing to its convenience and safety, in treating tibia plateau fractures.

The "Bankart knee": high-grade impression fractures of the posterolateral tibial plateau lead to increased translational and anterolateral rotational instability of the ACL-deficient knee.

The aim of this biomechanical cadaver study was to evaluate the effects of high-grade posterolateral tibia plateau fractures on the kinematics of anterior cruciate ligament (ACL)-deficient joints; it was hypothesized that, owing to the loss of the integrity of the osseous support of the posterior horn of the lateral meniscus (PHLM), these fractures would influence the biomechanical function of the lateral meniscus (LM) and consequently lead to an increase in anterior translational and anterolateral rotational (ALR) instability. Eight fresh-frozen cadaveric knees were tested using a six-degree-of-freedom robotic setup (KR 125, KUKA Robotics, Germany) with an attached optical tracking system (Optotrack Certus Motion Capture, Northern Digital, Canada). After the passive path from 0 to 90° was established, a simulated Lachman test and pivot-shift test as well as external rotation (ER) and internal rotation (IR) were applied at 0°, 30°, 60° and 90° of flexion under constant 200 N axial loading. All of the parameters were initially tested in the intact and ACL-deficient states, followed by two different types of posterolateral impression fractures. The dislocation height was 10mm, and the width was 15mm in both groups. The intraarticular depth of the fracture corresponded to half of the width of the posterior horn of the lateral meniscus in the first group (Bankart 1) and 100% of the meniscus width in the second group (Bankart 2). There was a significant decrease in knee stability after both types of posterolateral tibial plateau fractures in the ACL-deficient specimens, with increased anterior translation in the simulated Lachman test at 0° and 30° of knee flexion (p = 0.012). The same effect was seen with regard to the simulated pivot-shift test and IR of the tibia (p = 0.0002). In the ER and posterior drawer tests, ACL deficiency and concomitant fractures did not influence knee kinematics (n.s.). This study demonstrates that high-grade impression fractures of the posterolateral aspect of the tibial plateau increase the instability of ACL-deficient knees and result in an increase in translational and anterolateral rotational instability.

A Novel Locking Buttress Plate Designed for Simultaneous Medial and Posterolateral Tibial Plateau Fractures: Concept and Comparative Finite Element Analysis.

The complex tibial plateau fractures involving both medial and posterolateral columns are of frequent occurrence in clinics, but the existing fixation system cannot deal with medial and posterolateral fragments simultaneously. Therefore, a novel locking buttress plate named as medial and posterior column plate (MPCP) was designed in this study to fix the simultaneous medial and posterolateral tibial plateau fractures. Meanwhile, the comparative finite element analysis (FEA) was conducted to investigate the discrepancy between MPCP and traditional multiple plates (MP + PLP) in their biomechanical characteristics. Two 3D finite element models of simultaneous medial and posterolateral tibial plateau fracture fixed with MPCP and MP + PLP system, respectively, was constructed. To imitate the axial stress of knee joint in ordinary life, diverse axial forces with 100, 500, 1000, and 1500 N were applied in the two fixation models, and then the equivalent displacement and stress nephograms and values were obtained. The similar trend of displacement and stress increasing with the loads was observed in the two fixation models. However, several heterogeneities of displacement and stress distribution were found in the two fixation models. The max displacement and von Mises stress values of plates, screws, and fragments in the MPCP fixation model were significantly smaller than that in the MP + PLP fixation model, except for the max-shear stress values. As a single locking buttress plate, the MPCP system showed the excellent benefit on improving the stability of the simultaneous medial and posterolateral tibial plateau fractures, compared with the traditional double plate fixation system. However, the excessive shear stress around screw holes should be paid attention to prevent trabecular microfracture and screw loosening.

Clinical Outcomes ofFixation ofDepressed Posterolateral Tibial Plateau Fractures Using a Direct Lateral Approach.

Fixation of plateau posterolateral fracture (PLF) is challenging because the fracture site is mostly covered by vital neurovascular structures. We operated on 15 cases of PLF using a direct lateral approach. This study aims to report on clinical results. Between 2017 and 2019, 15 cases of PLFs were fixed with a direct lateral approach and a tricortical autologous bone graft from the iliac crest. A depression of more than 2mm was indicated for the surgical treatment. Clinical evaluation included Lysholm score, International Knee Documentation Committee Score (IKDC) score, and Tegner activity scale after two years follow-up. The last follow-up was at 24months after the operation. The mean postoperative Tegner activity scale did not change significantly compared to before the injury (6.5 (6-7) vs. 7 (6-8, p = 0.5)). The postoperative IKDC and Lysholm scores improved significantly compared to before the operation (p < 0.001). The full range of motion was seen in all patients except one who was manipulated after three months. Surgical treatment using a direct lateral approach is a safe procedure for PLFs that results in good, short-term clinical and radiologic outcomes without fibular osteotomy or compromising the important neurovascular structures. IV.

Medial Head of the Gastrocnemius Tenotomy Through a Posteromedial Approach Significantly Improves Surgical Accessibility of the Tibial Plateau.

Compare accessible area of the posterior tibial plateau through a modified posteromedial (PM) approach before and after tenotomy of the medial head gastrocnemius. We report the outcomes of 8 patients who underwent gastrocnemius tenotomy during PM approach. A modified PM approach was performed on 10 cadaveric legs, and the surgically accessible area was outlined. Next, a medial head gastrocnemius mid substance tenotomy was completed, and the accessible area was again outlined. Tibia specimens were imaged in a micro-CT scanner to measure accessible surface area and linear distance along the joint line. In addition, 8 patients who underwent tenotomy for tibial plateau fracture had outcomes recorded. The modified PM approach with tenotomy provided significantly more access to the posterior plateau than without tenotomy. The modified PM approach before tenotomy allowed access to 1774 mm 2 (SD = 274) of the posterior plateau surface and 2350 mm 2 (SD = 421, P < 0.0001) with tenotomy. A linear distance of 38 mm (SD = 7) and 57 mm (SD = 7, P < 0.00001) was achieved before and after tenotomy, respectively. In the clinical series, the average knee arc of motion was 116 degrees (95-135). The modified PM approach with medial head gastrocnemius tenotomy significantly improves surgical access to the posterior plateau. Patients who received tenotomy have acceptable functional outcomes. This cadaveric study provides an alternative approach for treatment of posterolateral tibial plateau fractures which may mitigate damage to neurovascular structures.

Feasibility of the modified inverted L-shaped approach for posterolateral tibial plateau fracture: A retrospective study.

Approaches for treating posterolateral tibial plateau fractures vary among surgeons, and the inverted L-shaped approach is a known option. This article aims to introduce a new modified posterolateral inverted L-shaped approach for isolated posterolateral tibial plateau fractures and study its feasibility. Medical records of patients with posterolateral tibial plateau fractures were reviewed. Plain radiographs were obtained during the follow-up period, and the hospital for special surgery (HSS) score was used to assess the function of the injured limb. Perioperative complications were recorded and followed-up. In total, 32 patients with posterolateral tibial plateau fractures were treated using a modified posterolateral approach. The mean age of the patients was 44 ± 11 years (28–64 years). All patients successfully underwent surgery and were followed-up for a mean duration of 13 ± 2 months (10–16 months). On plain radiographs, fracture lines were fuzzy 3 months after surgery and disappeared 12 months after surgery. No perioperative complications occurred during the follow-up period. The HSS score was evaluated 12 months after surgery, and the mean score was 91 ± 5 points (81–97 points), including 25 excellent cases and 7 good cases. The modified posterolateral inverted L-shaped approach has the advantages of small soft tissue dissection, fracture reduction under direct vision, easy internal fixation, and a lower risk of neurovascular injury. This approach is feasible for the treatment of isolated posterolateral tibial plateau fractures, and further high-quality randomized control trials are required to confirm its clinical efficacy.

The Incidence of Posterolateral Tibial Plateau and Central Lateral Femoral Condylar Impaction Fractures in a Pediatric and Young Adult Population.

Posterolateral tibial plateau and central lateral femoral condylar impaction fractures are known to occur in the setting of anterior cruciate ligament (ACL) tears. There have been no prior investigations into the incidence and morphology of posterolateral tibial plateau impaction fractures in the setting of ACL injury in a pediatric population. Patients between 9 and 22 years of age with knee magnetic resonance imagings (MRIs) performed demonstrating complete or partial ACL tear were included in this study. MRI reports were reviewed to denote the presence of posterior cruciate ligament, medial collateral ligament, or lateral collateral ligament injury, meniscus tears, cartilage lesions. MRIs were reviewed by 2 fellowship-trained orthopaedic surgeons to denote the presence of posterolateral tibial plateau and central lateral femoral condylar impaction fractures and physeal status of femoral and tibial physes. Statistical analysis performed included χ 2 analysis and the Student t testing. A total of 328 patients with a primary ACL tear were identified. The mean age of patients included was 16.5 years (range: 9.0-21.5). The incidence of posterolateral tibial plateau impaction fractures was 83/328 (25.3%) while the incidence of lateral femoral condylar impaction fractures was 119/328 (36.3%). Bipolar impaction fractures occurred in 37/328 (11.3%). Of the 83 tibial impaction fractures identified, 82 were low-grade morphologic subtypes. Patients with lateral tibial plateau impaction fractures were older than those with no fracture (17.2±2.2 vs. 16.3±2.1, P =0.001). Only 3/38 (7.9%) patients with an open tibial physis sustained a tibial plateau impaction fracture compared with 80/290 (27.6%) with a closed tibial physis (χ 2 value: 6.9, P =0.009). There was no difference in proportion of patients with lateral femoral condylar impaction fractures based on femoral physeal status ( P =0.484). The incidence of posterolateral tibial plateau impaction fractures in the setting of ACL tear in a pediatric and young adult patient population appears to be lower while lateral femoral condylar impaction fractures occur more frequently when comparing to previously reported incidences found in adult populations in the literature. Furthermore, posterolateral tibial plateau impaction fractures occur less frequently in those with an open proximal tibial physis and high-grade posterolateral tibial plateau bone loss is exceedingly rare in pediatric and young adult patients. Lateral femoral condylar impaction fractures are associated with lateral meniscal tears and medial meniscal ramp lesions. Level IV-cross-sectional study.

Treatment of posterolateral tibial plateau fractures with a novel lateral tibial plateau annular plate via fibular neck osteotomy approach

To investigate the effectiveness of a novel lateral tibial plateau annular plate (hereinafter referred to as the novel plate) fixation via fibular neck osteotomy approach for posterolateral tibial plateau fractures. Between January 2015 and December 2018, 22 patients with posterolateral tibial plateau fractures were treated. There were 10 males and 12 females with an average age of 39.0 years (range, 25-56 years). Seven fractures were caused by falls, 10 by traffic accidents, and 5 by falling from height. The time from injury to hospitalization ranged from 3 to 12 days, with an average of 7.0 days. All patients were closed fractures. According to Schatzker classification, the fractures were classified as type Ⅱ in 8 cases, type Ⅲ in 9 cases, type Ⅴ in 1 case, and type Ⅵ in 4 cases. The fractures were fixed with the novel plates after reduction via fibular neck osteotomy approach. The fracture reduction and healing were observed by X-ray film after operation. The range of motion of the knee joint was recorded and the function was evaluated by modified American Hospital for Special Surgery (HSS) score. All operations were completed successfully. The operation time was 60-95 minutes (mean, 77.6 minutes). The intraoperative blood loss was 100-520 mL (mean, 214.5 mL). There was 1 case of common peroneal nerve injury during operation and 2 cases of fat liquefaction of incision after operation. All patients were followed up 13-32 months (mean, 19.4 months). Postoperative X-ray films showed that the fracture reduction was good in 17 cases and moderate in 5 cases, and all fractures healed with a healing time of 10-18 weeks (mean, 13.0 weeks). At last follow-up, the range of motion of the knee joint ranged from 100° to 145° in flexion (mean, 125.5°) and from 0° to 4° in extension (mean, 1.2°). The modified HSS score was 82-95 (mean, 86.3). There was no complications such as plate deformation, screw fracture, fracture reduction loss, skin necrosis, and so on. For posterolateral tibial plateau fractures, the novel plate fixation via fibular neck osteotomy approach has the advantages of clear intraoperative field, firm fracture fixation, and less postoperative complications, which is beneficial to the recovery of knee joint function.