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

BACKGROUND

Fixing 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.

METHODS

Twenty-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.

RESULTS

Groups 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.

CONCLUSIONS

The 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.

Clinical Outcomes of Fixation of Depressed Posterolateral Tibial Plateau Fractures Using a Direct Lateral Approach

Introduction

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.

Material and methods

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 2 mm 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.

Results

The last follow-up was at 24 months 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.

Conclusions

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.

Level of evidence

IV.

Anatomical basis of the support of fibula to tibial plateau and its clinical significance

Background

The fibula is only indirectly involved in the composition of the human knee joint and has therefore been neglected in the research on knee osteoarthritis. Nonuniform settlement of the proximal tibia plateau is clinically defined as when the height of the medial tibial plateau is lower than that of the lateral side in medial compartment knee osteoarthritis (KOA). The non-uniform settlement of the proximal tibia plateau may be caused by fibular support on the lateral side. Orthopedic surgeons practice partial fibulectomy based on the clinical manifestation of nonuniform settlement, and this technique has been shown to reduce pain and improve function in patients with medial compartment KOA. However, this hypothesis of the mechanism of nonuniform settlement lacks an anatomical basis.

Methods

The P45 polyester plastination technique was used to prepare sections of the proximal tibiofibular joint to investigate the distribution of the bone trabeculae in the region of the lateral tibial plateau.

Results

There was uneven distribution of trabeculae in the lateral condyle of the tibia and the head and neck of the fibula. The fibula and the posterolateral cortex of the shaft of the tibia united to form an arch beam via the tibiofibular joint. Many thick, dense trabeculae were present in a longitudinal direction above the tibiofibular arch.

Conclusions

The fibula supports the lateral tibial plateau, and the trabeculae were concentrated above the tibiofibular arch.

Use of Osteochondral and Meniscal Allografts from Bone Cuts of Total Knee Arthroplasty for the Treatment of Tibial Plateau Malunions: A Case Series of Four Patients Showing Early Results

PURPOSE

Intra-articular malunion of tibial plateau fracture is a complex problem to treat. We are presenting outcomes of our series of patients of malunited tibial plateau fractures treated with osteo-chondro-meniscal allograft from lateral tibial plateau harvested from patients undergoing total knee arthroplasty (TKA).

METHODS

The technique was used in four patients. Preoperative computed tomography (CT) scan was used to match donor and recipient graft dimensions and to measure any malalignment. Patients were evaluated for Visual analogue Scale (VAS) for pain (scale 1-10 cm), WOMAC (Western Ontario McMaster Osteo-Arthritis Index) score, knee range of motion, and limb alignment.

RESULTS

There were three medial tibial plateau malunions and one lateral tibial plateau malunion. Articular comminution with depression was seen in all of them. One patient underwent concurrent high tibial osteotomy for the elevation of the medial tibial plateau and posterior cruciate ligament reconstruction was performed concurrently in one patient. All patients showed improvement in knee range of motion, WOMAC score, and VAS score for knee pain. Limb alignment improved in all cases. Radiologically there was consolidation of the allograft in all the cases at 6 months. The mean follow-up was 15.2 months (range 12-18 months).

CONCLUSION

Osteochondral allograft can be a good choice for reconstructing large articular cartilage defects in tibial plateau malunions. Osteo-chondro-meniscal grafts obtained during TKA can be a viable alternative for reconstructing such defects with excellent early clinical, functional, and radiological outcomes.

LEVEL OF EVIDENCE

IV.

Sagittal knee kinematics in relation with the posterior tibia slope during jump landing after an anterior cruciate ligament reconstruction

Purpose

An increased posterior tibia plateau angle is associated with increased risk for anterior cruciate ligament injury and re-rupture after reconstruction. The aims of this study were to determine whether the tibia plateau angle correlates with dynamic anterior tibia translation (ATT) after an anterior cruciate ligament reconstruction and whether the tibia plateau angle correlates with aspects of knee kinematics and kinetics during jump landing.

Methods

Thirty-seven patients after anterior cruciate ligament reconstruction with autograft hamstring tendon were included. Knee flexion angle and knee extension moment during single leg hops for distance were determined using a motion capture system and the dynamic ATT with its embedded method. The medial and lateral posterior tibia plateau angle were measured using MRI. Moreover, passive ATT was measured using the KT-1000 arthrometer.

Results

A weak negative correlation was found between the maximal dynamic ATT and the medial tibia plateau angle (p = 0.028, r = − 0.36) and between the maximal knee flexion angle and the lateral tibia plateau angle (p = 0.025, r = − 0.37) during landing. Patients with a smaller lateral tibia plateau angle show larger maximal knee flexion angle during landing than the patients with larger lateral tibia plateau angle. Also, the lateral tibia plateau angle is associated the amount of with muscle activity.

Conclusion

The posterior medical tibia plateau angle is associated with dynamic ATT. The maximal knee flexion angle and muscle activity are associated with the posterior lateral tibia plateau angle.

Level of evidence

III

Correlation between the mid-substance cross-sectional anterior cruciate ligament size and the knee osseous morphology

INTRODUCTION

One of the final goals of anatomical anterior cruciate ligament (ACL) reconstruction is the restoration of native anatomy. It is essential to obtain more accurate predictors of mid-substance ACL size before surgery. However, to the best of our knowledge, no study has reported correlation between the mid-substance cross-sectional ACL size and the knee osseous morphology. The purpose of this study was to reveal correlation between the mid-substance cross-sectional ACL size and the knee osseous morphology.

MATERIALS AND METHODS

We used 39 non-paired formalin fixed Japanese cadaveric knees. All surrounding muscles, ligaments and soft tissues in the knee were resected. After soft tissue resection, the knee was flexed at 90°, and a tangential plane of the femoral posterior condyles was marked and cut the ACL. Femoral ACL footprint size, Blumensaat's line length, lateral wall of the femoral intercondylar notch size, lateral wall of the femoral intercondylar notch height, tibial ACL footprint size, tibia plateau size, the whole anterior-posterior (AP) length, the medial and the lateral AP length of the tibia plateau, and the medial-lateral (ML) length of the tibia plateau were measured. The Pearson's product movement correlation was calculated to reveal correlation between the mid-substance cross-sectional ACL size and the measured parameters of the knee osseous morphology.

RESULTS

The measured mid-substance cross-sectional ACL size was 49.9 ± 16.3 mm². The tibial ACL footprint size, the tibia plateau size, the whole AP length of the tibia plateau, the lateral AP length of the tibia plateau and the ML length of the tibia plateau were significantly correlated with the mid-substance cross-sectional ACL size.

CONCLUSIONS

For clinical relevance, some tibial sides of the knee osseous morphology were significantly correlated with the mid-substance cross-sectional ACL size. It might be possible to predict the mid-substance ACL size measuring these parameters.

Two-stage late reconstruction with a fresh large osteochondral shell allograft transplantation (FLOCSAT) for a large ostechondral defect in a non-union after a lateral tibia plateau fracture 2-year follow up

This is the description of a 58-year-old female patient presenting 8 months after a horse riding accident with significant pain and inability to walk independently. Imaging revealed a large osseous defect of the lateral tibia plateau which was not united posteriorly. The patient refused knee replacement and we developed a patient specific two-step procedure for her. Step 1: Filling of the defect with a large cortico-cancellous autograft from the posterior iliac crest; step 2: Transplantation of a fresh large osteochondral shell allograft (FLOCSAT). The postoperative protocol included continuous passive motion (CPM), partial weight bearing for three months, and physiotherapy. Based on the concept of immuno-privileged cartilage tissue, the patient did not get any immuno-suppressive therapy. Pain-, activity of daily living, Lysholm and Tegner scores were evaluated before defect filling surgery with autograft, before allograft transplantation, and at 12 and 24 months after allograft transplantation. There were no complications. Radiographic analyses with plain films and CT scans revealed solid osseous integration within 3 month. The patient regained excellent functionality in both, activities of daily living and sports (back to horse riding, trampolin jumping). Knee arthroscopy after 1year showed excellent condition of the lateral meniscus and the cartilage of the lateral tibia plateau. Chimerism/DNA analysis of a cartilage biopsy showed, that at 1year 32% of the donor cells have been already replaced by the patient's own cells. To our knowledge, this is the first case of a patient who sustained such a large defect during a tibia plateau fracture, and got successfully treated with a fresh large osteochondral shell allograft transplantation in a two-step procedure.

Posterior tibial plateau fracture: a new treatment-oriented classification and surgical management

PURPOSE

To establish a classification system for the different types of posterior tibial plateau fractures (PTPF), and to explore the fracture patterns and early results of treatment.

METHODS

39 PTPFs patients who received surgeries through posteromedial or (and) posterolateral knee approaches were analyzed retrospectively.

RESULTS

There were 5 types of PTPFs identified in the new classification system: posteromedial split fracture (type I, 7 patients), posterolateral split fracture (type II, 5 patients), posterolateral depression fracture (type III, 11 patients), posterolateral split and depression fracture (type IV, 2 patients), and posteromedial split combined with posterolateral depression fracture (type V, 14 patients). All patients underwent surgeries safely without complications. The average follow up was 18.1 months (12-30 months). The average weight-bearing durations were 15.6 weeks (12-20 weeks). Based on Rasmussen functional scoring system, 20 cases were regarded as excellent, 14 were good, 5 were fair, and 0 was poor. There was significant change in the Rasmussen functional score before (8.38 ± 2.87) and after surgery (24.20 ± 3.44). According to Rasmussen radiology system, 28 cases were excellent, 8 cases were good, 3 were fair, and none was poor. There was also a significant difference detected between pre-operation (6.77 ± 2.27) and post-operation (16.41 ± 2.65).

CONCLUSION

This study presents a new classification system for the different types of PTPFs based on the treatment. The classification is clinically relevant and can be used to guide the surgical management.