Morphologic study of posterior articular depression in Schatzker IV fractures

Schatzker IV tibial plateau fractures: are they always unicondylar?

Objective

The objectives of this study were to describe the incidence and morphology of medial tibial plateau fractures that extend into the lateral articular surface and to describe trends in their management.

Design

Retrospective.

Setting

Level I Urban Trauma Center.

Patients

Seventy consecutive patients sustaining OTA/AO 41 B1 and B3 fractures.

Intervention

Open reduction internal fixation of medial tibial plateau fractures.

Main Outcome Measurements

Incidence of medial tibial plateau fractures that extend into the lateral articular surface. Secondary outcomes include localization of lateral articular surface depression, neurovascular injury, and trends in surgical management.

Results

Seventy patients were included with 9 fractures (12.9%) isolated to the medial condyle (MC) and 61 fractures (87.1%) extending to the lateral condyle (LC). Compartment syndrome was present in 2 patients (2.9%), peroneal nerve palsy in 2 (2.9%), and arterial injury in 1 (1.4%). Initial external fixation was used more frequently in the LC group compared with the MC group (P = 0.028). Of the 61 fractures in the LC group, 49 (80.3%) included lateral articular surface depression which localized to the posteromedial quadrant of the lateral articular surface in 36 of 49 fractures (73.5%). Lateral articular surface depression depth ≥10.6 mm was associated with the use of dual incisions (P < 0.001).

Conclusions

Schatzker IV fractures frequently extend to the lateral condyle and often present with depression of the posteromedial lateral articular surface. Fractures with lateral articular surface depression depth ≥10.6 mm were more likely to undergo fixation with dual incisions.

Level of Evidence

Therapeutic level IV.

The Relationship between the Injury Mechanism and the Incidence of ACL Avulsions in Schatzker Type IV Tibial Plateau Fractures: A 3D Quantitative Analysis Based on Mimics Software

INTRODUCTION

 Tibial plateau fractures are often accompanied with ligamental and meniscal injuries. Among which, the combined existence of Schatzker type IV fracture with anterior cruciate ligament (ACL) avulsion has been reported rarely. The purpose of this study was to determine the injury mechanism of Schatzker type IV fracture with ACL avulsion based on Mimics software.

METHODS

 Ninety-nine Schatzker type IV tibial plateau fractures were retrospectively analyzed by quantitative three-dimensional measurements. ACL avulsions were diagnosed through the data of computed tomography and magnetic resonance imaging. We simulated the knee posture when an injury occurred and defined different injury patterns. The chi-square test was used for determining the main mechanism which causes Schatzker type IV fractures associated with ACL avulsions.

RESULTS

 There were more ACL avulsions and more displaced ACL avulsions associated with the knee in flexion in the setting of Schatzker type IV fracture (p < 0.05). More ACL avulsions were found in the injury pattern of flexion-valgus than the other injury patterns of the same level (p < 0.05). The rotation of the tibial showed no significant difference in producing ACL avulsion fractures.

CONCLUSION

 This study found that a flexed knee at the occurrence of a Schatzker type IV tibial plateau fracture is a high-risk factor for causing associated ACL avulsion and producing more displaced avulsions. Flexion-valgus pattern was the main cause of Schatzker type IV fractures associated with ACL avulsions. The findings will help orthopedists understand the injury mechanism and enhance their awareness of such injuries to avoid unfavorable prognosis.

Analysis of medial tibial plateau fracture injury patterns using quantitative 3D measurements

BACKGROUND

The Wahlquist system classifies tibial medial plateau fractures into three types based on the sagittal fracture line location, with type C at highest risk of complications. However, the injury mechanism of tibial medial plateau fractures, especially tibial rotation movement, remains unclear. The purpose of the present study was to determine the injury patterns of medial tibial plateau fractures using 3D model simulation and quantitative 3D measurements.

METHODS

Seventy-eight consecutive AO/OTA type 41-B tibial plateau fractures were retrospectively analyzed using CT-based 3D models and quantitative 3D measurements. The knee posture at the moment of fracture occurrence was simulated, and various knee angles in the sagittal, coronal, and axial planes were measured to evaluate the mechanism of medial tibial plateau fracture. The mean valgus-varus, hyperextension-flexion, and internal-external rotation angles were determined, and the chi-square test was used for comparisons of categorical varus and valgus force data to determine the main force direction in Wahlquist type C fractures.

RESULTS

Angle measurements in the coronal planes showed that 28 (35.9%) medial tibial plateau fractures resulted from a varus injury pattern, while 50 fractures (64.1%) resulted from a valgus pattern. Valgus force produced significantly more Wahlquist type C fractures (37 of 50 fractures) than varus force (2 of 28 fractures) (p < 0.05). There was no significant difference in the cases of patients with type C fractures between the tibial internal and external rotation injury patterns(P > 0.05).

CONCLUSIONS

Valgus force was the cause of 64.1% of the medial tibia plateau fractures in the present cohort. Furthermore, valgus force produced more Wahlquist type C fractures than varus force. The present findings will help orthopedists understand the injury mechanism of the Wahlquist classification system, and will facilitate the identification of the common features of medial tibial plateau fractures induced by specific injury patterns.

The prevalence of soft tissue injuries in operative Schatzker type IV tibial plateau fractures

BACKGROUND

To describe the incidence of soft-tissue injuries in patients with surgically treated Schatzker type IV tibial plateau fractures.

METHODS

All tibial plateau fractures in skeletally mature patients treated operatively between January 2013 and August 2018 were retrospectively reviewed using a clinical medical record system. All fractures were categorized according to the AO/OTA classifications. Twenty-seven patients with Schatzker type IV tibial plateau fractures were further classified based on the Wahlquist classification. Associated soft-tissue injuries, which consisted of cruciate ligament injuries, and meniscal and collateral ligament injuries, were diagnosed through operation notes and magnetic resonance imaging (MRI) data. The categorical variables were tested by the chi-square test or Fisher's exact test.

RESULTS

The incidence of lateral meniscus tears and medial meniscus tears was 63% and 44.4% in Schatzker type IV tibial plateau fractures, respectively. Twenty-five (92.6%) patients had sustained anterior cruciate ligament (ACL) injuries, and 19 (70.4%) patients had an incomplete injury of the posterior cruciate ligament (PCL). There were 17 (63%) lateral collateral ligament (LCL) injuries, and 8 (29.6%) medial collateral ligament (MCL) injuries. Using the Wahlquist classification, these fractures were categorized as follows: type A, one patient; type B, six patients; type C, twenty patients. There was no significant difference between the type of fracture and the location of soft tissue injuries.

CONCLUSIONS

This study found that operative Schatzker type IV tibial plateau fractures represented a high incidence of soft-tissue injuries, especially LCL injuries, ACL injuries, and meniscus tears. Based on our data, we believe that soft-tissue injuries in operative Schatzker type IV tibial plateau fractures deserve more attention.

Medial sided articular impaction in tibial plateau fractures

INTRODUCTION

Tibial plateau fractures are a heterogenous group of injuries with a variable amount of articular injury and are commonly associated with lateral sided articular impaction. Previous work has focused on describing the morphology of tibial plateau fractures, but has neglected description of medial sided articular impaction. The aim of this investigation was to assess the morphology of medial sided articular impaction in tibial plateau fractures, with specific attention directed toward the frequency, location, size, and associated fracture patterns.

METHODS

Skeletally mature patients presenting to a Level I trauma center from 2008-2018 with a tibial plateau fracture (AO/OTA 41B-C) were identified retrospectively. Fractures were classified by AO/OTA and Schatzker type. Radiographs and computed tomography (CT) scans were reviewed to identify and localize medial sided articular impaction. The location and surface area of impaction was characterized by creating frequency diagram heat maps from axial CT scans. Descriptive statistics were performed using standard measures.

RESULTS

Of the 1032 tibial plateau fractures included, 82 (7.9%) were noted to have medial sided articular impaction. Rate of impaction varied by fracture type (p = 0.03): Schatzker II, 2% (7 of 381); Schatzker IV, 21% (19 of 96); and Schatzker VI, 11% (56 of 524). Average total surface area of impaction was 9% of the total and 19% of the medial plateau area. Area of impaction varied by fracture type (p = 0.004): Schatzker II, 6% (95% confidence interval [CI], 4%-7%); Schatzker IV, 11% (95% CI, 9%-13%), and Schatzker VI, 9% (95% CI, 7%-11%). The area of impaction occurred primarily along the lateral aspect of the medial plateau in Schatzker II fractures, in the anteromedial quadrant of Schatzker IV fractures, and was evenly distributed across the medial plateau in Schatzker VI fractures.

CONCLUSIONS

Surgeons should be aware that medial articular impaction is present in approximately 8% of tibial plateau fractures. Schatzker IV fractures are most likely to have medial impaction and a larger proportion of the joint surface involved in these injuries.

3D mapping and classification of tibial plateau fractures

Aims

Tibial plateau fractures (TPFs) are complex injuries around the knee caused by high- or low-energy trauma. In the present study, we aimed to define the distribution and frequency of TPF lines using a 3D mapping technique and analyze the rationalization of divisions employed by frequently used classifications.

Methods

In total, 759 adult patients with 766 affected knees were retrospectively reviewed. The TPF fragments on CT were multiplanar reconstructed, and virtually reduced to match a 3D model of the proximal tibia. 3D heat mapping was subsequently created by graphically superimposing all fracture lines onto a tibia template.

Results

The cohort included 405 (53.4%) cases with left knee injuries, 347 (45.7%) cases with right knee injuries, and seven (0.9%) cases with bilateral injuries. On mapping, the hot zones of the fracture lines were mainly concentrated around the anterior cruciate ligament insertion, posterior cruciate ligament insertion, and the inner part of the lateral condyle that extended to the junctional zone between Gerdy’s tubercle and the tibial tubercle. Moreover, the cold zones were scattered in the posteromedial fragment, superior tibiofibular syndesmosis, Gerdy’s tubercle, and tibial tubercle. TPFs with different Orthopaedic Trauma Association/AO Foundation (OTA/AO) subtypes showed peculiar characteristics.

Conclusion

TPFs occurred more frequently in the lateral and intermedial column than in the medial column. Fracture lines of tibial plateau occur frequently in the transition zone with marked changes in cortical thickness. According to 3D mapping, the four-column and nine-segment classification had a high degree of matching as compared to the frequently used classifications.

Cite this article: Bone Joint Res 2020;9(6):258–267.

Subdivision of injured area for Schatzker IV tibial plateau fracture repair: A report of 12 cases

BACKGROUND

Treatment of Schatzker IV tibial plateau fractures is challenging due to the wide variety of potential fracture morphologies and injury to multiple ligaments. Subdivision of the injured area into three zones may simplify the preoperative plan. In this study, we reported 12 cases of Schatzker IV tibial plateau fracture that were treated with pre-operative plans based on a new subdivision of the injured area.

METHODS

From January 2012 to April 2016, 12 patients with a Schatzker IV tibial plateau fracture were treated in our hospital with preoperative plans guided by the new sub-division method. Clinical and radiological results were evaluated during follow-up.

RESULTS

In all cases, the incisions healed without skin necrosis, and the average Lysholm knee score was 73 points (range, 53-90) at the final follow-up.

CONCLUSION

Sub-division of the injured area represented a useful strategy for preoperative surgical planning in the treatment of Schatzker IV tibial plateau fractures.

Correlation of Fracture Energy With Sanders Classification and Post-traumatic Osteoarthritis After Displaced Intra-articular Calcaneus Fractures

OBJECTIVES

To quantify fracture severity for a series of displaced intra-articular calcaneal fractures (DIACFs) and to correlate it with Sanders classification, post-traumatic osteoarthritis (PTOA), and patient outcomes.

DESIGN

Retrospective review and fracture severity analysis.

SETTING

Level 1 trauma center affiliated with the University of Iowa in Iowa City, IA.

PATIENTS/PARTICIPANTS

Thirty-six patients with 48 DIACFs were selected from 153 patients previously treated. All patients 18 years of age and older who had available electronic preop and postop computed tomography (CT) scans, good-quality postop and follow-up radiographs, and a follow-up ≥18 months were selected for study.

INTERVENTION

Fractures were treated with percutaneous reduction, using multiple small stab incisions and fluoroscopy to guide manipulation of articular fragments using cork screws or Steinmann pins, with subsequent fixation using 3.5- and 4.0-mm screws.

MAIN OUTCOME MEASUREMENTS

Preop CT scans were used to grade fractures according to the Sanders classification and to quantify fracture severity. Fracture severity was objectively quantified using a CT-based measure of fracture energy. PTOA was assessed on follow-up radiographs using the Kellgren-Lawrence scale. Patient outcomes were assessed using the Short Form 36 (SF-36) questionnaire and a visual analog scale pain score.

RESULTS

Fracture energies for the 48 DIACFs ranged from 14.1 to 26.2 J (19.3 ± 3.1 J) and correlated with Sanders classification (rho = 0.53, P = 0.0001); type I (16.3 ± 0.9 J); type II (18.0 ± 2.7 J); type III (20.8 ± 2.8 J); and type IV (22.0 ± 0.7 J). Fracture energy was higher for fractures in which the subtalar joint developed PTOA (19.5 ± 2.7 J) than for those that did not (18.9 ± 3.3 J), but the difference did not reach statistical significance. The Sanders classification predicted PTOA risk [odds ratio (OR) = 4.04, 95% confidence interval = 1.43-11.39, P = 0.0084]. No relationship was observed between fracture energy and visual analog scale pain scores. Higher fracture energy correlated with lower SF-36 scores.

CONCLUSIONS

Fracture energy positively correlates with Sanders classification for DIACFs, which can be used to identify more severe fractures at greater risk of progressing to PTOA.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Classification of tibia plateau fracture according to the "four-column and nine-segment"

PURPOSE

The existing classification systems of tibial plateau fracture (TPF) are suboptimal for clinical use and academic communication. A more comprehensive and universal classification system with the capability to analyze all patterns of TPF is urgently required to guide the clinical practice. This study aimed to analyze the incidence and fracture characteristics of TPF using a computed tomography-based "four-column and nine-segment" classification.

METHODS

According to the differentiated morphological characteristics, tibial plateau and proximal fibula were divided into four columns, which were subdivided into nine segments. Tibia plateau injury index (TPII) was innovatively introduced to represent the extent of injury. A total of 698 consecutive adult patients with 704 affected knees were included (377 females, 321 males, mean age 51.6 ± 12.9 years). Fracture mapping was retrospectively analyzed according to the new-style classification system based on the CT imaging.

RESULTS

371 (53.2%) left knees and 321 (46.0%) right knees were injured solely and 6 (0.9%) cases sustained bilateral injuries. The rates of one-column, two-column, three-column and all-four-column injuries were 30.5%, 31.5%, 28.0% and 9.9%, respectively. On average, 2.2 ± 1.0 columns and 3.6 ± 2.1 segments were involved, the mean TPII was 5.7 ± 3.0. The rates of mild, moderate and severe comminuted fractures were 50.0%, 37.5% and 12.5%. The most frequently affected columns were lateral column (572, 81.3%) and intermedial column (524, 74.4%), and the less frequently involved columns were the medial column (219, 31.1%) and fibular column (218, 31.0%). The most frequently affected segments were the posterolateral segment (465, 66.1%), anterolateral segment (453, 64.3%) and posteromedian segment (379, 53.8%). The least frequently involved segment was tubercle segment (85, 12.1%).

CONCLUSIONS

The novel "four-column and nine-segment" classification will be a beneficial classification system for clinical diagnosis, statistical analysis and prognostic judgment of tibial plateau fractures.

A systematic literature review of tibial plateau fractures: What classifications are used and how reliable and useful are they?

INTRODUCTION

Classification systems such as the Schatzker and AO/OTA have been proposed for standardised assessment of tibial plateau fractures and to guide clinical decision making. However, there has been no comprehensive literature review of all classification systems for tibial plateau fractures, including assessment of their reliability. The aim of this systematic review was to identify and appraise previously established classification systems for tibial plateau fractures and determine their reliability for fracture classification.

METHODS

Six databases were searched from inception until October 2016. Classification systems for tibial plateau fractures were identified. No restriction was placed on imaging modality (plain film X-ray, CT, MRI). Data synthesis was performed to identify common features of the systems, their prevalence within the literature and studies of intra and inter-rater reliability of fracture classification using Kappa coefficient (κ).

RESULTS

Thirty-eight classification systems were identified, five of which were a sub-classification of a single fracture type from a previous tool. The Schatzker and AO/OTA classification systems were the most commonly reported. Of the tools identified only five have been tested for inter and intra-observer reliability (Schatzker, AO/OTA, Duparc, Hohl and Luo). Reliability of more simplistic classification systems, such as that by Luo et al. (three-column) was typically high (intra-κ = 0.67-0.81, inter-κ = 0.71-0.87), but with the disadvantage of providing less information on fracture patterns and morphology. Intra and inter-observer reliability using plain film X-ray was frequently moderate (κ = 0.40-0.60), with 2D and 3D CT typically improving reliability of classification. Only 11 of the 32 complete classification systems identified association of fracture classification with clinical outcome.

DISCUSSION

Frequently used systems for classification of tibial plateau fractures display moderate intra and inter-observer reliability. More sophisticated imaging modalities such as 2D and 3D CT typically improve reliability estimates. Using fracture classification based on imaging findings to predict clinical outcome was not a commonly reported goal of newly developed systems. More detailed assessment of fracture patterns and morphology, in conjunction with information on surgical fixation, may be desirable for predicting outcomes and to guide clinical decision making.