Occult posterior malleolar fractures (PMFs) associated with tibial shaft fractures are thought to occur most commonly in spiral fracture types of the tibia. We hypothesize that tibial diaphyseal fracture patterns would be associated with certain PMFs, highlighting the pathomechanics of the injury.

A retrospective review was performed on data collected between 1 January 2013 and 9 November 2020. The inclusion criteria were patients aged over 16 years with a diaphyseal tibial fracture who had undergone a CT of the affected lower limb. The Mason and Molloy posterior malleolar fracture classification system was used to describe the morphology of the PMFs.

There were 764 diaphyseal fractures identified. Of these, 442 met the inclusion criteria. A total of 107patients (24.21%) had PMF extensions. The classification of the PMFs according to Mason and Molloy revealed eight type 1 fractures (7.48%), 60 type 2A (56.07%), six type 2B (5.61%), and 33 type 3 fractures (30.84%). The most common PMF seen in this study was the minor rotational pilon (type 2A). PMFs generally occur in combination with spiral diaphyseal fractures (42A1, 42B1, 42C1, and 43A1). The majority of PMFs were undisplaced pre-surgical intervention. Only the 2B subtype (major rotational pilon) had a significant association with fracture displacement.

This study highlighted an association between spiral tibial shaft fractures and type 2A posterior malleolus fractures. Unlike the PM fractures of the ankle, the majority of PM fractures associated with tibia fractures are undisplaced. We theorize that unlike the force transmission in ankle fractures, where the rotational force is in the axial plane in a distal-proximal direction, in the PM fractures related to tibia fractures, the rotational force in the axial plane progresses from proximal-distal. Therefore, the force transmission which exits posteriorly, finally dissipates the force and is thus unlikely to displace.

The presence of a fracture of the posterior malleolus gives a poor prognosis for ankle fractures. This study aimed to analyze the anatomical structures at risk in the traditional postero-medial (TPM) approach.

Of a total of 21 cadaveric pieces, 11 were female and 10 were male; 9 ankles/right foot and 11 ankles/left foot. The age of the specimens ranged between 66 and 98 years. The following statistical tests were performed: Median, Mean, SD and Mann Whitney non-parametric test.

The p values associated with the statistical tests were calculated, obtaining all p values lower than the level of significance. Therefore, there is statistically significant evidence to reject the null hypothesis, that is, there is a difference in the medians of men and women, with respect to the 3 measurements. The evaluation of the anatomical structures at risk allowed us to measure the distance of the Posterior Tibial nerve, thus demonstrating that the approach was 20 mm above could cause injury. The difference in the measurements obtained between men and women had statistical significance.

Using the TPM (traditional postero-medial) approach it is possible to identify a large portion of the posterior malleolus both laterally and medially. The evaluation of the anatomical structures at risk allowed us to measure the distance of the Posterior Tibial nerve, thus demonstrating that the approach was 20 mm. above could cause injury. The difference in the measurements obtained between men and women had statistical significance. We intend to quantify visualization percentages using computed tomography in our next study.

Guidelines for treatment of posterior malleolar fragments (PMFs) in trimalleolar fractures are scarce, mainly based on retrospective studies, and show varying advice. The need for fixation of smaller (< 25%) PMFs remains particularly controversial. This study aims to evaluate the superiority of fixation of medium-sized PMFs versus no fixation of the fragment.

A multicentre randomized controlled trial was conducted between January 2014 and January 2022 in two Dutch level 1 trauma centres (protocol registration: NCT02596529). Patients presenting with an AO-44-B3 fracture with a medium-sized (5% to 25%) PMF were 1:1 randomized online between open reduction and internal fixation (ORIF) (FIX) versus no fixation (NO-FIX) of the fragment. A total of 41 patients were allocated online to FIX via the posterolateral approach and 40 patients to NO-FIX. The primary outcome was functionality measured by the American Academy of Orthopaedic Surgeons (AAOS) questionnaire one year postoperatively. Secondary outcomes were osteoarthritis (OA) measured on radiographs and the Olerud and Molander ankle score, visual analogue scale pain, and EuroQol five-dimension questionnaire during follow-up. Quality of reduction was assessed by step-off on postoperative CT scan and radiograph. Complications were recorded.

After one-year follow-up, no difference (p = 0.141) in AAOS was found after FIX (median 90 (IQR 68 to 95)) and NO-FIX (median 93 (IQR 85 to 97)). OA (≥ grade 2) was present in four (17%) of the cases after FIX and five (20%) after NO-FIX (p = 0.763). After one year, median pain scores were 20 (IQR 5 to 40) versus 10 (IQR 5 to 25) (p = 0.032), and perceived general median health scores were 80 (IQR 60 to 89) versus 83 (IQR 71 to 90) (p = 0.596) after FIX and NO-FIX, respectively. Postoperative step-off > 1 mm on CT scan was present in 56% after FIX versus 71% after NO-FIX (p = 0.193). Complication rates were 18% versus 5% (p = 0.071) after FIX and NO-FIX, respectively.

ORIF of medium-sized posterior fragments in AO type B trimalleolar fractures does not prompt superior functional or radiological results after one-year follow-up. Longer follow-up is needed to evaluate intermediate or long-term effects.

Geriatric ankle fracture management requires a comprehensive approach that balances appropriate patient optimization, fracture reduction, stability, and early mobilization. Surgical and nonsurgical options should be cautiously considered based on patient and fracture characteristics. Early weight-bearing treatment options should be pursued when possible. There are a myriad of treatment options including fibular intramedullary devices or minimally invasive joint prep tibiotalocalcaneal nailing that minimize soft tissue disruption and can provide robust stability sufficient to allow early weight-bearing postoperatively when appropriate. It is essential for geriatric patient treatment teams to optimize outcomes and minimize complications in this often-challenging patient population.

Unstable ankle injuries often comprise multiple fracture lines; including a posterior malleolus fracture in up to 40% of cases. Surgical fixation of such injuries often requires multiple incisions. The configuration of the posterior malleolus fracture can also vary greatly, and the presence of this fracture is known to poorly affect patient outcomes. In this paper, the authors describe a modified posterolateral approach to the ankle which provides three windows for fixation of complex ankle fractures.

Background Surgical fixation of posterior malleolar fractures (PMFs) has traditionally been guided by fragment size. Recent studies have proposed fragment morphology as a more effective determinant for optimal fixation. To determine the optimal strategy for PMFs, we conducted a radiographic review of our patients. Methods Between January 2016 and December 2019, all adult patients with ankle fractures who underwent surgical fixation at our institution were reviewed (n=648). The exclusion criteria included pilon fractures, tumors, or infections causing neuromuscular dysfunction, insufficient follow-up, bilateral involvement, and prior injuries. After applying these criteria, 110 eligible patients remained for the study. They were further categorized on the basis of treatment type (non-fixation, screw, and plating) and fracture classification system (Haraguchi, Lauge-Hansen, and Weber classifications). The fracture fragment involvement was further classified as large (>25% of the articular surface) or small (<25%). The outcomes were evaluated via the modified Kellgren-Lawrence grade and the final malleolar step-off to assess osteoarthritis severity and fixation stability. Results Compared to non-fixation treatment, surgical intervention was associated with better outcomes in the Haraguchi type 1, supination-external rotation (SER), and pronation-external rotation (PER) groups. Additionally, surgical fixation using plates resulted in a lower step-off rate compared to screws. Notably, patients with small-fragment fractures who underwent surgical fixation exhibited outcomes comparable to or more favorable than those with larger fragments. These findings suggest that fracture morphology with size may have greater prognostic significance than fragment size alone. Conclusion This study on PMFs highlights that fracture morphology, rather than fragment size alone, should guide surgical decision-making for PMFs. Different PMF patterns call for personalized surgical strategies. Compared with screw fixation and non-fixation treatment, plate fixation yields superior outcomes, particularly in terms of joint space narrowing and stability. This study advocates for a morphology-based approach to managing PMFs, prioritizing plate fixation to achieve better results.

Fractures of the upper ankle joint are frequent injuries and part of routine clinical trauma surgery. In recent years, treatment strategies have changed in different ways due to advances in imaging diagnostics and a better understanding of the biomechanics. In addition, new implant systems are available. The goals of the reconstruction are anatomical reduction with restoration of the joint anatomy, reconstruction of the length, rotation and axial relationships as well as the restoration of stable joint guidance. In addition to the bony reconstruction, the focus is on restoring ligamentous instabilities. Keywords that are increasingly more in focus and controversial are: the posterior malleolar fragment, syndesmosis instability, the fourth malleolus and the importance of the deltoid ligament. For a good long-term result, anatomical reconstruction remains the basic requirement, regardless of the methods used.

A delay in diagnosis and management of syndesmotic injuries can result in a complex treatment challenge, leading to poorer clinical results and higher rates of unplanned, syndesmotic-related primary operations and reoperations. This article presents a simple and reproducible algorithm with case examples for the management of syndesmotic injuries with delay in diagnosis to help guide surgeons when determining the best treatment strategies for this complex injury.

Background: The operative indication for posterior malleolar fracture (PMF) remains controversial. This study aimed to assess the midterm outcomes of PMF treatment for developing a treatment strategy for each morphological type. Methods: In this retrospective analysis, patients undergoing operative treatment for an unstable ankle fracture involving PMF were included after at least 3 years of follow-up. PMFs were classified by fracture morphology according to the Haraguchi classification. This study divided the entire cohort into three independent populations based on the types of PMF. For each population, patients were further categorized into two groups depending on whether PMF was surgically fixed or not, and comparisons were made between these two groups. Demographic data, functional and radiographical outcomes were compared between two groups in each of the three populations. Results: With a total of 472 patients, the mean patient age was 45.8 years, and the mean follow-up was 51 months. For type 1 fracture, a total of 237 cases were found. Quality of reduction by CT (QRC) was mostly good in both groups (83.6% vs. 83.3% in the non-fixation vs. fixation group, respectively, p = 0.269). Functional and radiological outcomes between both groups showed no significant difference. For type 2 PMFs, a total of 199 cases were found, and QRC was significantly different between the two groups (good grade, 5.4% vs. 60.7% in the non-fixation vs. fixation group, respectively, p < 0.001). The radiological and clinical outcomes of the PMF fixation group were statistically superior to those of the non-fixation group (both p < 0.001). For type 3 fractures, a total of 36 cases were found. In all the cases in this group, surgical fixation of PMF was not performed. Only the syndesmosis instability was analyzed as a viable factor to be considered for achieving favorable surgical outcomes. PMF fixation group showed significantly more postoperative complications (24.4% vs. 40.4%, non-fixation vs. fixation, respectively, p < 0.001). Major complications in the fixation group were deep wound infection (6.8%), superficial peroneal nerve injury (6.8%), and hallux flexion deficit (5.0%). Conclusions: Different treatment strategies seem to be required for each PMF morphological subtype. Further studies with more detailed designs for each PMFs are warranted for more clinically related results that are helpful for making practical surgical decisions.

The aim of the study is to compare the mechanical stability of posterior malleolar fractures fixed with different screw types and locking plates in the management of trimalleolar ankle fractures using the finite element (FE) method.

An FE model containing the distal tibia, fibula, talus, and calcaneus was created based on the computed tomographic images of a healthy man without any musculoskeletal disorders. The medial, lateral, and posterior malleoli were segmented using three virtual planes to create a trimalleolar fracture model, with the posterior malleolar fracture fragment comprising approximately 30% of the articular surface. Four different fixation approaches, including two partial thread cannulated screws (PTS), two full thread cannulated screws (FTS), and L-shaped (LLP) and T-shaped (TLP) locking plates with screws, were used to fix the posterior malleolar fracture. Two partial thread screws and a locking plate along with screws were used to fix the medial and lateral malleolar fractures, respectively. Two different loading conditions, namely static axial load and Achilles tendon force, were considered in the simulation.

Under axial load, the maximum gap opening distance of the posterior malleolar fracture with screws only was obviously larger than that with locking plates. The maximum gap distance was 0.12 mm, 0.08 mm, 0.04 mm, and 0.05 mm in the PTS, FTS, LLP, and TLP, respectively. Under Achilles tendon force, the maximum gap opening distance were 0.12, 0.1, 0.03, and 0.1 mm, in the PTS, FTS, LLP, and TLP, respectively, under Achilles tendon force.

The results suggest that locking plates offer greater stability and reduce the fracture gap opening for posterior malleolar fractures involving 30% of the distal tibial articular surface in the fixation of trimalleolar ankle fractures.

The purpose of this study was to introduce and evaluate the Descriptive Ankle Fracture Classification (DAFC) system, a novel alphanumeric method for categorizing ankle fractures and fracture dislocations, and to assess its reliability and prognostic value compared to traditional classification systems (AO/OTA, Weber, and Lauge-Hansen).

A retrospective review was conducted on 90 patients who underwent surgical treatment for ankle fractures. Four observers of varying experience levels classified the fractures using the DAFC, AO/OTA, Weber, and Lauge-Hansen classification systems. Interobserver and intraobserver reliability were evaluated using Fleiss' Kappa coefficient. Functional outcomes were assessed with the American Orthopaedic Foot & Ankle Society (AOFAS) and Olerud Molander Ankle Score (OMAS) systems, and comparisons were made across classification systems to determine prognostic value.

The DAFC system demonstrated superior interobserver reliability, particularly for medial malleolus fractures (Kappa = 0.935-0.954) and syndesmotic injuries (Kappa = 0.873-0.891), compared to the other systems. Intraobserver reliability was consistently high across all categories in the DAFC system, with Kappa values ranging from 0.967 to 1.000. Functional outcomes revealed significant associations with the DAFC classification: patients with complete dislocation (D2) had significantly lower AOFAS and OMAS scores than those without dislocation (D0) (P = 0.011), and those with larger posterior malleolus fractures (P2) had poorer OMAS scores (P = 0.014). No statistically significant differences in AOFAS or OMAS scores were observed across AO/OTA, Weber, or Lauge-Hansen classifications.

The DAFC system offers a reliable and comprehensive framework for ankle fracture classification, with the added benefit of prognostic insights, particularly regarding dislocation and posterior malleolus involvement. Its high interobserver and intraobserver reliability, even among observers with varying experience, suggests that the DAFC system is valuable for clinical use. Future research should focus on validating these findings in larger cohorts and assessing the DAFC system's impact on long-term patient outcomes.

Level IV, Retrospective cohort.

Isolated posterior malleolar fracture is a rare condition, and this fracture is usually overlooked and diagnosed as an ankle sprain owing to a lack of awareness and difficulty in diagnosis. Posterior ankle impingement syndrome (PAIS) is relatively common in athletes and is usually caused by trauma or overuse. The impingement occurs due to repeated compression of a bony or soft tissue. Here, we report a rare case of a 17-year-old rugby player presenting with posterior ankle impingement caused by nonunion of an isolated posterior malleolar fracture. This patient was treated using a posterior ankle arthroscopic excision. At 16 weeks postoperatively, his ankle and hallux pain disappeared, and he returned to sports activities with no morbidities related to the surgical procedure. Based on a computed tomography scan, the bone fragment causing the impingement was resected, and the union of the residual posterior malleolar fragment was verified.

Posterior malleolus fractures may be fixed to restore syndesmosis stability. However, these fractures are often accompanied by ruptures of other ligaments that stabilize the syndesmosis. This study investigates the frequency of anterior syndesmosis injury in posterior malleolus fractures and its effect on rotational stability.

Seventy-five consecutive patients who underwent surgery for ankle fractures involving posterior malleolus were prospectively included. Preoperative computed tomography scans in two planes (transverse and sagittal) were used to assess the presence and size of avulsion fractures (LeFort-Wagstaffe and Tillaux-Chaput). Intraoperatively, anterior syndesmosis injuries and rotational stability (determined via the external rotation test) were assessed through direct visualization.

In 73 patients (97%), a complete injury of the anterior tibiofibular ligament was observed intraoperatively, manifesting as avulsion fractures (8%), ligament injuries (44%), or a combination of both (45%). The mean dimensions of the avulsion fractures were 12.6 mm × 7.5 mm for LeFort-Wagstaffe fractures and 12.4 mm × 7.9 mm for Tillaux-Chaput fractures. Posterior malleolus fractures were stabilized in 57 patients. In 52 of these cases (92%), syndesmosis instability in the direction of external rotation persisted despite fixation of the posterior malleolus.

Fixation of posterior malleolus fractures is rarely sufficient to fully restore syndesmosis stability. Post-fixation assessment of syndesmosis stability, particularly in external rotation, is essential.

Isolated posterior malleolar (PM) fractures are rare fractures without consensus regarding treatment decisions and functional outcomes. The study aims to compare the clinical and radiological results of patients treated surgically or conservatively for isolated PM fractures.

The study included 30 patients who presented with an isolated PM fracture and were treated conservatively (n = 15) or with surgery (n = 15). The two groups were compared regarding demographic data, clinical results, and radiological outcomes. The effect of PM fragment size covering less than or more than 25% of the joint surface on clinical and radiological outcomes was also evaluated.

The Ankle Fracture Scoring System (AFSS), Visual Analog Scale (VAS), and satisfaction scores of the patients in the surgical group were determined to be better than those of the conservatively treated group (p = 0.015, p = 0.029, p = 0.021). A higher rate of osteochondral lesion (OCL) in the talus was observed in the surgical group (p = 0.007). In the patients with fracture size > 25%, the AFSS-1, VAS, and patient satisfaction scores were found to be better in the surgical group than in the conservative group (p = 0.004, p = 0.036, p = 0.014), with no difference determined between the groups in respect of the OCL rate.

Independently of the fracture size, surgical treatment of patients with PM fracture provides better clinical results. It does not change the joint ROM however may increase the OCL rate. While surgical treatment does not affect the clinical results in patients with a fracture size smaller than 25%, it positively affects the clinical results in patients with a larger fracture size.

Level IV, retrospective cohort study.

The aim of this study was to compare plain lateral radiographs and 3D surface rendering (SR) CT imaging, in the characterization of posterior malleolar fracture (PMF) morphology using the Mason and Molloy classification. The null hypothesis was that there was no difference in characterization of morphology between plain radiographs and 3D SR CT.

Morphology of the PMF was categorized initially by the CT scan as classified by Mason and Molloy on 180 trimalleolar ankle fractures. PM fracture fragment size on the lateral radiograph were compared to their respective 3D surface rendering CT reconstructions, by two independent observers. Morphology of the PMF was assessed using all preoperative radiographs as compared to 3D SR CT.

On comparison of fracture fragment morphology, all fractures had poor categorization by plain radiographs although rotational pilon fractures (type 2A and 2B fractures) had the worse sensitivity and specificity (below 33% and below 50%, respectively). Radiographs underestimated joint involvement in type 2B fracture patterns because of the underappreciation of the posteromedial fragment.

This study shows that the use of plain radiographs to categorize morphology of PMFs is poor. The study adds to the ever-growing body of evidence on the inaccuracy of using plain radiographs in PMFs to plan treatment. Additional CT imaging is imperative to allow for appropriate treatment planning in the management of PMF. Smaller fracture fragments are more susceptible to inaccuracies, especially the rotational pilon subtypes (2A and 2B) because of the obliquity of the posteromedial fragment to the plane of the X-ray source.

Level III, retrospective comparative study.

There is evidence that the presence of a posterior malleolus fracture (PMF) worsens the prognosis of ankle fractures, making conservative treatment a poor choice. PMFs include a heterogeneous group of bone injury patterns that are sometimes associated to medial malleolus extensions, as well as fibula fractures or syndesmotic damage. This requires the surgeon to be well-versed in anatomy to choose the appropriate surgical approach. This study examines the relationship between the visualization of the distal posterior tibial surface through a Traditional Postero-Medial (TPM) approach in a simulated fracture pattern equivalent to Bartonícek type III fractures previously studied with axial CT images.

This is an experimental analytical cross-sectional anatomical study. Twenty fresh-frozen adult cadaveric ankle/foot specimens preserved at - 27 ºC at the University of Barcelona School of Medicine were examined. The traditional posteromedial approach was performed for each specimen, then anatomical measurements were performed. Subsequently, a Bartonícek type III fracture pattern was designed and generated for each of them. Finally, the anatomical view was correlated with axial CT images for each one and the fracture pattern was assessed. Measurements of Anatomical Visualization Surface (AVS), Total width of the Posterior M. (TWPM), Imaging Visualization Surface (IVS) and the Total Imaging Viewing Surface (TIVS) were recorded. Univariate and bivariate analysis was performed. The mean, standard deviation (SD), minimum and maximum values were calculated. The Intraclass Correlation Coefficient (ICC) was calculated.

Of the 20 specimens, 9 were female and 11 male, with 8 right and 12 left specimens, aged between 65 and 95 years. The average Anatomical Visualization Surface (AVS) was 24.1 ± 7.49 mm. The average of the total width of the posterior muscle (TWPM) was 30.55 ± 7.19 mm. While the average visualization was 77 ± 11 %. The average Imaging Visualization Surface was 30.23 ± 6.1 mm. The average Total Imaging Visualization Surface was 37.53 ± 3.45 mm. While the average of visualization in CT was 80 ± 11 %. A degree of agreement (CCI) was obtained with a value of 0.667 CI 95 % (0.1773-0.8672). That is, the CCI is considered good (CCI value between 0.4 and 0.75).

The TPM approach is a valid alternative for surgical access and visualization of the PM, including complex Bartonícek type III fractures. The TPM approach achieves axial visualization of the distal posterior tibial plafond of 77 ± 11 %.

The Bartoníček/Rammelt classification is established for posterior malleolar fractures. It subdivides the fractures into 5 types and outlines treatment recommendations. This study aims to determine the intraobserver and interobserver reliability of the Bartoníček/Rammelt classification and investigates its applicability regarding treatment recommendations.

Computed tomography (CT) scans of 80 ankle fractures with a posterior malleolar fracture were analyzed by four observers at two different time points 30 days apart (d1 and d2). Intrarater and interrater reliability was measured using kappa values. The corresponding surgery rates of the fracture subtypes were analyzed, and the surgery rates were correlated with fragment sizes and displacements.

A moderate interobserver reliability for d1 0.41 (CI 0.35-0.47) and d2 0.42 (CI 0.36-0.48) was detected. Intraobserver reliability was documented as perfect, with a mean kappa of 0.83. Type II fractures were operated on in 50% of cases. In 50% of type II cases, a nonoperative treatment was chosen. Fragment size correlated strongly with the chosen therapy, and osteosynthesis was performed significantly more often when the fragment size exceeded 3 cm3 (P < .01).

The Bartoníček/Rammelt classification system showed moderate interobserver reliability and perfect to substantial intraobserver reliability. In clinical practice of this study cohort, the size of the posterior malleolar fragment rather than the dislocation and joint impaction seemed to have the decision to operate on type II or III fractures. Existing treatment recommendations based on the Bartoníček/Rammelt classification correspond to the therapy algorithm carried out in this cohort of patients.Levels of Evidence: Level III: Retrospective study.

Fractures involving the ankle joint typically manifest as bimalleolar or trimalleolar fractures, with isolated posterior malleolus fractures (IPMF) representing a rare subset, comprising 0.5-4 % of cases. Due to its rarity and subtle clinical presentation, IPMF poses unique diagnostic and management challenges. This case report presents the diagnosis and treatment of a 50-year-old woman with an IPMF following a fall, alongside a review of relevant literature.

A 50-year-old woman presented with severe right ankle pain and inability to bear weight after a backward fall. Physical examination showed swelling, tenderness in the medial retromalleolar region, and pain with passive dorsiflexion. Imaging through X-rays and CT scans revealed an isolated posterior malleolus fracture involving 40 % of the tibiotalar articular surface. The patient underwent surgical fixation using two posteroanterior cannulated screws via a posterolateral approach. Post-operative X-rays confirmed adequate reduction and fixation. She remained non-weight-bearing for six weeks, followed by physical therapy.

IPMFs are challenging to diagnose due to subtle signs and limitations of standard radiographs. Advanced imaging, particularly CT with 3D reconstruction, is crucial for accurate diagnosis. Classification systems, such as Haraguchi and Mason, guide treatment. Surgical fixation is often necessary for fractures involving significant joint surfaces, displacement, or instability. Posteroanterior cannulated screws offer a minimally invasive and effective stabilization method, as demonstrated in this case.

Early recognition and proper surgical management of IPMF are essential to prevent complications. Increased awareness and further research are needed to improve outcomes for this rare ankle injury.

Throughout the musculoskeletal system, fracture patterns and subsequent healing rely partly on bone density. In the foot and ankle, bone density has been shown to play a role in supination and external rotation fracture patterns. Adding to previous research, this investigation examines the association between bone density and trimalleolar versus trimalleolar equivalent fracture patterns following pronation and external rotation injuries using computed tomography (CT)-derived Hounsfield units (HU).

A retrospective chart review was conducted among patients without a history of fracture or osteoporosis who sustained a PER IV fracture. Demographic data were collected. Fractures were separated between PER IV equivalent and fracture groups. CT-derived HU was assessed at the distal tibia and fibula. Density was compared between PER IV equivalent and fracture groups and among posterior malleolar fracture patterns.

Seventy-five patients met the selection criteria, with 17 comprising the equivalent group and 58 in the fracture group. There were 38 type 1, 9 type 2, and 11 type 3 posterior malleolus fractures. The ankle bone density of the PER fracture equivalent group (331.98 ± 65.71HU) was greater than the PER fracture group (281.61 ± 76.99HU; P = .008). A statistically significant difference in tibial bone densities among equivalent and all PER fracture types (P = .01) with the equivalent group (331.98 ± 65.71HU) maintaining a greater tibial bone density than the type 2 posterior malleolus fracture group (252.35 ± 57.33HU; P = .009).

Higher bone density was associated with PER IV equivalent fractures; however, there was no density difference among posterior malleolus fracture types. When presented with PER IV fractures, consider fixation that addresses a lower bone density.

III.

For rotational ankle fractures with a posterior malleolus fracture (PMF), the decision to further evaluate the ankle injury with computed tomography (CT) is challenging. The objective of this study is to determine how well PMF fracture size on x-rays correlates with size on CT, and how well x-rays can predict which patients receive PMF fixation after CT review.

This is a retrospective study of adult ankle fractures with PMFs that had preoperative radiographs and CT imaging over a 5-year period. PMF x-ray and CT measurements were recorded, and relationships between x-ray measurements and final PMF fixation plan after CT review were evaluated.

A total of 98 patients were identified with both x-rays and preoperative CT imaging. Pearson's rank correlation demonstrated a strong relation between PMF width percentage measured on x-ray and CT (r = 0.724). Of the 45 patients with a PMF size under 20% on x-ray, only one patient (with an apparent incarcerated fragment) underwent PMF fixation after review of the CT.

PMF width on lateral x-ray correlates well with CT size and is sensitive for predicting the need for dedicated posterior malleolus based on one institutional practice pattern. Below 20% fracture width on lateral x-ray, a dedicated CT rarely leads to a decision to perform PMF fixation. Limiting pre-operative CT to those with PMF width >20% could reduce CT utilization by as much as 45% without negatively affecting patient care.

Level III: Diagnostic.

Large posterolateral tibial fragments, known as Volkmann fractures, are common in ankle fracture-dislocations and typically require open reduction and fixation with interfragmentary screws and often buttress plates using a prone posterolateral approach. In this setting, fibula plating often necessitates dissection of the lateral window between the peroneal tendons and the skin, increasing wound-related complications. In recent years, intramedullary nailing of fibula fractures has gained popularity as a minimally invasive technique that allows load-sharing stabilization. However, this procedure has traditionally been performed in the supine position, which can pose challenges if a Volkmann-type fracture is present, requiring repositioning and losing access to the fibula through the posterolateral approach. Our objective is to describe a technique for fixing ankle fracture-dislocations with large posterolateral fragments using tibial buttress plates and fibula nails through a prone posterolateral approach without dissecting the lateral window. Additionally, we will present a case series with preliminary results.

Background: Zero echo time (ZTE) imaging is a relatively new magnetic resonance (MR) pulse sequence that provides bone-soft tissue contrast similar to that of computed tomography (CT). Purpose: We sought to (1) determine the accuracy of ZTE MRI for the diagnosis of common ankle fractures and (2) investigate whether ZTE imaging sequences are equivalent to the gold standard of CT for the characterization of fracture fragments. Methods: We conducted a prospective case series of 54 patients with acute ankle trauma, in whom ZTE MRI was performed, followed by surgical reduction. Fractures on the ZTE sequence were correlated with the operative report as the reference standard. Raw agreement (%) and correlation (κ) were calculated. Selected fracture fragments were measured in 2 dimensions (anterior-posterior and superior-inferior) on corresponding sagittal ZTE and CT images by 3 independent radiologists to determine reliability. Results: The ZTE sequence demonstrated 47 distal fibular, 17 medial malleolar, 24 posterior malleolar, 5 anterior talofibular ligament avulsion, and 4 distal tibial fractures on the 54 cases. Raw agreement with operative findings was 95% (range: 86%-100%) and correlation almost perfect (0.960 [0.926-0.995]). Fragment characterization was accurate and repeatable. Intraobserver and interobserver agreement was excellent. Conclusions: Our case series suggests that the use of the MRI ZTE sequence may provide images with CT-like contrast for characterizing acute ankle fractures.

Posterior malleolus fractures (PMFs) are challenging injuries around the ankle that can lead to poor clinical outcomes as they can compromise ankle stability. Although there has been an evolution in the principles of management of PMFs, their optimal treatment remains controversial. This review article aims to provide an in-depth account of the management of PMF, thereby providing a better understanding of these complex cases hence resulting in improving patient outcomes.

Introduction A trimalleolar fracture is a complex unstable fracture that usually occurs as the result of rotational injuries of the ankle. Management and understanding of these fractures have evolved greatly over the last decade. Our study aimed to assess the postoperative outcomes following the fixation of these fractures using fragment-specific low profile anatomical fixation implants. Methods We retrospectively analyzed patients admitted to our multidisciplinary team unit with a trimalleolar fracture between October 2021 and February 2024. Each fracture was classified using CT imaging and subsequently fixed using fragment-specific implantation (VolitionTM). In the postoperative period, patients were followed up and assessed functionally and radiologically. Results A total of 40 skeletally mature patients were included in this study, each requiring surgical fixation for a tri-malleolar ankle fracture. Patient-reported outcome data collected showed an average Manchester-Oxford Foot Questionnaire (MOXFQ) score of 34.3 (±24.6) and a Foot and Ankle Disability Index (FADI) score of 77.9 (±22.1). All but one fracture successfully achieved radiological union with a mean time to union of 7.4 weeks (5-16 weeks). Conclusions Our study is an early demonstration of the promising results that can be observed through the use of fragment-specific low-profile anatomical fixation. Further comparative studies would provide a further understanding of the effectiveness.

Distal tibia shaft fractures have a high association with posterior malleolar fractures (PMFs); hence, a preoperative ankle CT scan is commonly obtained. The purpose of this study was to determine whether a CT scan for distal third tibia shaft fractures is associated with differences in recognition of a posterior malleolus fracture (PMF), treatment of an identified PMF, outcomes, and postoperative complications.

We retrospectively reviewed cases of adult patients with distal third tibia shaft fractures treated with an intramedullary nail between 2018 and 2020. Patients were divided into 2 groups based on whether they received a preoperative ankle CT scan. Outcomes included surgical time, the rate of missed PMFs or postoperative PMF displacement, the treatment of the PMFs, postoperative weight-bearing restrictions, Patient-Reported Outcomes Measurement Information System Global-10 (PROMIS Global-10) scores, and unplanned revision surgeries.

124 patients (age 45 ± 18 years; 39.5% female) with distal third tibia shaft fractures treated with intramedullary nailing and with minimum 6 months of follow-up were reviewed. 26 patients received preoperative CT scans, and 98 patients did not have CT scans. The rate of detected PMF was 69.2% (N = 18) in patients with CT and 55.1% (N = 54) in patients without CT (P = 0.19). No significant differences were observed in all outcomes between the 2 groups (P > 0.05). 3 PMFs not visible on radiographs were identified on CT, and they did not require fixation and did not displace. PMFs that were greater than one-third of the joint surface were more likely to have a preoperative CT (P < 0.01).

Preoperative CT scans for distal third tibia shaft fractures may be useful in characterizing large PMFs; however, this knowledge does not translate into shorter surgical time, increased fixation rates, decreased unplanned revision surgery, or improved patient-reported outcomes. Discovery of PMFs did not always lead to fixation, and PMFs without fixation did not become further displaced.

Background Ankle fractures, particularly those involving the posterior malleolus, are prevalent injuries that can lead to significant functional impairment if not managed appropriately. The choice of surgical approach for posterior malleolus fixation - posteromedial (PM) or posterolateral (PL) - remains a debate among orthopedic surgeons. The PM approach is a traditional technique involving extensive soft tissue dissection, while the PL approach offers improved visualization and precision with potentially less soft tissue disruption. Materials and methods  This prospective comparative study was conducted at the Department of Orthopedics, Dr. D. Y. Patil Hospital and Research Centre, Pune, between February 2022 and August 2024.A total of 42 patients with trimalleolar fractures involving the posterior malleolus were randomly assigned to either the PL or PM surgical groups, with 21 patients in each group. Surgical outcomes were assessed using the American Orthopedic Foot and Ankle Society (AOFAS) scores, articular surface step-off, range of motion (ROM), and complications such as osteoarthritis, infection, neurovascular injury, nonunion, and deep vein thrombosis at six months, 12 months, and final follow-up. Results Patients in the PL group demonstrated superior clinical outcomes with higher mean AOFAS scores at six-month (87.52 ± 2.92) and 12-month (90.28 ± 1.72) follow-ups compared to the PM group (84.95 ± 3.25 at six months; 88.86 ± 2.41 at 12 months), with statistically significant differences favoring the PL approach. However, as per the final follow-up, the difference in AOFAS scores between the two groups was not statistically significant. The PL group also had more patients with excellent ROM and fewer complications, such as arthritis, than the PM group. Conclusion  The PL approach for posterior malleolus fixation in trimalleolar fractures offers superior early functional outcomes and fewer complications than the PM approach. However, the long-term outcomes between the two approaches show no significant difference, indicating that both techniques can be effective depending on the specific fracture pattern and patient characteristics.

The purpose of this study was to define the utility of CT scans for detecting articular extension in tibial shaft fractures and determine whether radiographic parameters can predict the presence of operative distal tibial articular fractures (DTAFs).

Retrospective cohort study.

Single level I trauma center.

Patients age 18 years and older who were treated operatively for tibial shaft fractures occurring at or below the tibial isthmus were included. Patients were excluded for extension of the main tibial shaft fracture into the tibial plafond (AO/OTA 43 B/C), ballistic injuries, and absence of a preoperative CT scan.

The primary outcome was CT utility, defined as the presence of a DTAF or DTAF displacement on CT that was not recognized on plain radiographs on secondary analysis at the time of the study by a senior-level resident. Secondary outcome was the association between radiographic parameters and operative DTAFs. Variables with P ≤ 0.2 on univariate testing were included in a multiple binary logistic regression model to determine independent predictors of operative DTAFs.

One hundred forty-four patients were included, with a mean age of 52 years. Seventy-six patients (53%) were men. CT utility was 41% for the identification of unrecognized DTAFs. CT utility was 79% for isolated pDTAF, 57% for medial DTAF, 83% for isolated anterolateral DTAF, and 100% for multiple DTAFs. Operative DTAFs were independently associated with spiral tibial shaft fracture type (P < 0.001) and low fibular fracture (P = 0.04). In patients who had both spiral tibial shaft fracture type and low fibula fracture, the rate of operative DTAF was 46% (22/48).

CT scans identified DTAFs that were unrecognized on plain radiographs in 41% of cases. CT scans were most useful in identifying nonposterior DTAFs. CT scans may be considered for all distal third tibial fractures, but especially those with spiral tibial shaft patterns and low fibular fractures, to avoid missing operative articular injury.

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

Paediatric triplane fractures and adult trimalleolar ankle fractures both arise from a supination external rotation injury. By relating the experience of adult to paediatric fractures, clarification has been sought on the sequence of injury, ligament involvement, and fracture pattern of triplane fractures. This study explores the similarities between triplane and trimalleolar fractures for each stage of the Lauge-Hansen classification, with the aim of aiding reduction and fixation techniques.

Imaging data of 83 paediatric patients with triplane fractures and 100 adult patients with trimalleolar fractures were collected, and their fracture morphology was compared using fracture maps. Visual fracture maps were assessed, classified, and compared with each other, to establish the progression of injury according to the Lauge-Hansen classification.

Four stages of injury in triplane fractures, resembling the adult supination external rotation Lauge-Hansen stages, were observed. Stage I consists of rupture of the anterior syndesmosis or small avulsion of the anterolateral tibia in trimalleolar fractures, and the avulsion of a larger Tillaux fragment in triplanes. Stage II is defined as oblique fracturing of the fibula at the level of the syndesmosis, present in all trimalleolar fractures and in 30% (25/83) of triplane fractures. Stage III is the fracturing of the posterior malleolus. In trimalleolar fractures, the different Haraguchi types can be discerned. In triplane fractures, the delineation of the posterior fragment has a wave-like shape, which is part of the characteristic Y-pattern of triplane fractures, originating from the Tillaux fragment. Stage IV represents a fracture of the medial malleolus, which is highly variable in both the trimalleolar and triplane fractures.

The paediatric triplane and adult trimalleolar fractures share common features according to the Lauge-Hansen classification. This highlights that the adolescent injury arises from a combination of ligament traction and a growth plate in the process of closing. With this knowledge, a specific sequence of reduction and optimal screw positions are recommended.

This study aimed to compare the findings of plain radiography and computed tomography (CT) of foot and ankle in patients submitted to the emergency department with high-energy foot and ankle trauma, to demonstrate if missing fractures on plain radiographs will significantly alter the treatment plan considered for each patient based on the findings of each imaging modality. We retrospectively observed standard radiological foot and ankle x-rays and CT scans in patients who presented to our center from April 2019 to June 2020 with a history of foot and ankle trauma with either loss of consciousness, a history of high-energy trauma, or clinical presentation disproportionate to plain radiographic findings. We investigated the number of fractures of each bone detected on plain radiographs and CT scans and the treatments based on each modality's findings in patients admitted to our center. Sixty-five out of 163 (39.87%) included in our study had at least one missed fracture on plain radiography that was detected on CT. Thirty-one (19%) patients had normal radiography despite actually having fractures. In 38 (23.31%) patients CT changed the treatment plan decided by our surgeons (P < 0.001). The two imaging modalities had a moderate agreement for detecting foot and ankle fractures overall (κ = 0.432). The failure to detect fractures in patients with high-energy trauma can significantly impact treatment effectiveness. Integrating CT scans into the diagnostic process can lead to changes in treatment planning and ultimately improve patient outcomes. LEVEL OF CLINICAL EVIDENCE: IV.

Posterior pilon fracture is speculated to occur by a combination of rotation and axial load, which makes it different from rotational posterior malleolar fracture or pilon fracture, but is not validated in vitro. The aim of the current study is to investigate the injury mechanisms of posterior pilon fracture on cadaveric specimens.

Eighteen cadaveric specimens were mounted to a loading device to undergo solitary vertical loading, solitary external rotational loading, and combined vertical and external rotational loading until failure, in initial position of plantarflexion with or without varus. The fracture characteristics were documented for each specimen.

Vertical loading force combined with external rotation force diversified the fracture types resulting in pilon fracture, tibial spiral fracture, rotational malleolar fracture, talar fracture or calcaneal fracture. Vertical violence combined with external rotational loading in position of 45° of plantarflexion and 0° of varus produced posterior pilon fracture in specimens No. 13 and 14.

Combination of vertical and external rotational force in plantarflexion position on cadaveric specimens produce posterior pilon fracture.

The Chaput fragment, a bony avulsion of the anterolateral margin of the distal tibia, is a less commonly discussed fracture pattern in ankle injuries. Its significance in ankle fractures and the optimal fixation technique remains unclear due to limited literature. This study aims to describe the morphology of ankle fractures with Chaput fragment and introduce a new classification system.

We retrospectively analyzed 33 patients with ankle fractures with associated Chaput fragment treated at our institute over a 3-year period. Data on patient demographics, fracture classification, surgical approach, and fixation method were collected, and a novel classification system for Chaput fragments was proposed.

Four distinct morphological types of Chaput fragment were identified (types 1-4), and three newer variants of trimalleolar fractures were identified (anterior, lateral, and medial variants). Type 1 refers to a small avulsion fragment attached to the anterior-inferior tibiofibular ligament; Type 2 is an anterolateral oblique type; Type 3 refers to an anterolateral fragment with extension into the medial malleolus and Type 4 is a comminuted Chaput fragment. Type 1 Chaput fragment was the most prevalent (60.6%), followed by Type 2 (24.3%), Type 4 (9.1%), and Type 3 (6.1%). The fixation methods ranged from screw fixation, plate fixation, and suture fixation to combinations of these techniques or even indirect stabilization with syndesmotic screws.

Our new classification system based on morphology includes all possible variants of Chaput fracture. This preliminary data needs to be corroborated by more studies and validated by a larger number of observers.

Ankle fractures are one of the more common musculoskeletal injuries that are treated by foot and ankle specialists. A thorough understanding of managing these injuries requires the ability to differentiate between stable and unstable fractures. The current literature supports the nonoperative management of stable Weber B ankle fractures, whereas unstable fractures have much better outcomes with surgical intervention. Specifically, we review the fixation strategies for the lateral, medial, and posterior malleolar fractures respectively. Finally, we discuss the current trends in postoperative management of some of the more common fracture patterns, and the safety in early weight-bearing protocols.

The indications for reduction and fixation of the posterior malleolus component of rotational ankle fractures have been controversial for nearly a century. This study aims to identify the historical basis for surgical intervention and trace trends in management strategies over time.

In March 2023, a systematic review of full-text, English-language articles providing indications for surgical fixation of the posterior malleolus component of rotational ankle fractures was performed. Articles underwent title and abstract screening before undergoing full-text review.

Historical indications for surgical fixation were size-dependent, with fractures comprising 25 % to 33 % of the plafond recommended for internal fixation. Modern studies suggest that nonoperative management of posterior malleolus fractures below this threshold results in residual malreduction of the articular surface, syndesmotic instability, and an increased need for independent fixation of the syndesmosis.

Size-based indications for posterior malleolus fracture fixation are based on Level V evidence from small retrospective case series published nearly one century ago and should be retired. While the size of the posterior malleolus component cannot be ignored, additional factors like fracture morphology and location within the plafond should guide modern surgical indications. Contemporary studies indicate that reduction and fixation of small posterior malleolus fractures (comprising less than 25 % of the articular surface) are associated with improved articular reductions, tibiotalar contact pressures, syndesmotic stability with decreased need for independent fixation of the syndesmosis, and superior postoperative outcomes.

The aim of this study was to describe the incidence and a complex pathoanatomy of posterior malleolus fractures in a Maisonneuve fracture.

The study included 100 prospectively collected patients with a complete clinical and radiological documentation of an ankle fracture or fracture-dislocation including a fracture of the proximal quarter of the fibula.

A posterior malleolus fracture was identified in 74 patients, and in 27% of these cases it carried more than one quarter of the fibular notch. Displacement of the posterior fragment by more than 2 mm was shown by scans in 72% of cases. Small intercalary fragments were identified in 43% of cases. Fractures of the Tillaux-Chaput tubercle were identified in 20 patients.

Our study has proved a high rate of posterior malleolus fractures associated with a Maisonneuve fracture, and documented their considerable variability in terms of involvement of the fibular notch, tibiotalar contact area, direction of displacement and frequency of intercalary fragments. Of no less importance is a combination of Tillaux-Chaput fractures with a Maisonneuve fracture.

To demonstrate how the use of adjunctive Computed Tomography (CT) can modify diagnosis, treatment options, and operative planning of ankle fractures in comparison with conventional radiographs (CR) in isolation.

A total of 53 patients diagnosed with an ankle fracture between 2011 and 2016, were assessed with CT and CR. Evaluations of the fractures using CR in isolation and CR combined with CT were compared using different readers. Fractures were assessed in terms of type, displacement, size, associated injuries, treatment, patient position and surgical planning.

The medial malleolus fractures characteristics (posteromedial fragment and anterior colliculus), the presence of posterior malleolus fracture and its characteristics (displacement, size, posteromedial or posterolateral segment) (ps < 0.042), syndesmosis injury (p < 0.001), and the absence of deltoid ligament lesion (p < 0.001), were more evident with the combination of CT and radiographs. There was an increase in operative indication (p = 0.007), prone positioning (p = 0.002), posterior malleolus surgical treatment (p < 0.001), posterolateral approach for the lateral malleolus (p = 0.003), and syndesmosis fixation (p = 0.020) with the association of CT and CR, among all groups of expertise, with a high interobserver reliability (> 0.75).

The CR may fail to demonstrate subtle lesions, such as posterior malleolus fractures and syndesmotic injuries. The CT evaluation increases the diagnostic precision and improves the quality of information the surgeon receives, what might positively affect patient care.

Retrospective Comparative Study.

Treatment of posterior malleolar (PM) ankle fractures remains controversial. Despite increasing recommendation for small PM fragment fixation, high quality evidence demonstrating improved clinical outcomes over the unfixated PM is limited. We describe the long term clinical and radiographical outcomes in younger adult patients with PM ankle fractures managed without PM fragment fixation.

A retrospective cohort study was performed on PM ankle fracture patients aged 18-55 years old admitted under our orthopaedic unit between 1st of April 2009 and 31st of October 2013. Inclusion criteria were ASA 1 and 2, independent mobility pre-trauma, no pre-existing ankle pathologies, with satisfactory bimalleolar and syndesmotic stabilisation. Open fractures, talar fractures, calcaneal fractures, pilon fractures, subsequent re-injury and major complications were excluded. All PM fragments were unfixated. Clinical outcomes were evaluated using visual analogue scale (VAS) for pain, Foot and Ankle Ability Measure (FAAM) with activities of daily living (ADL) and sports subscale for function, and patient satisfaction ratings. Osteoarthritis was assessed using modified Kellgren-Lawrence scale on follow-up weightbearing ankle radiographs.

Sixty-one participants were included. Mean follow-up was 10.26 years. Average PM size was 16.2 ± 7.39%. All participants were evaluated for clinical outcomes. Mean score of FAAM-ADL was 95.5 ± 7.13, FAAM-Sports 86.4 ± 15.5, patient satisfaction 86.2 ± 14.4% and pain score 1.13 ± 1.65. Radiographical outcomes were evaluated in 52 participants, showing no-to-minimal osteoarthritis in 36/52 (69%), mild osteoarthritis in 14/52 (27%) and moderate osteoarthritis in 2/52 (4%). Pain and functional scores were independent of PM fragment size, post-reduction step-off, dislocation, malleoli fractured or syndesmotic injury. PM step-off more than 1 mm and traumatic dislocation/subluxation were associated with worse radiographical osteoarthritis.

After controlling for confounders, the unfixated smaller posterior malleolus fragment at 10-year follow-up demonstrated largely satisfactory clinical outcomes with some radiographical progression of osteoarthritis.

Level III - Retrospective cohort study.

Foot and ankle surgeons are commonly confronted with the surgical dilemma on when and how to best surgically address trimalleolar ankle fractures with a posterior malleolar component. This may involve either direct fixation of the posterior malleolus or indirect stabilization with the fixation of the medial and lateral malleoli and trans-syndesmotic fixation. Recently there has been a paradigm shift in the management of these injuries with a more thorough understanding of anatomy, stability, and long-term sequela of these injuries. This article aims to evaluate the current literature on posterior malleolar ankle fractures, approaches to fixing the posterior malleolus, and outcomes and complications of these procedures.

This study aims to elucidate the pathology of PMFs in the South African population, establish correlations between fracture patterns and international classification guidelines and evaluate the interobserver reliability of current classifications.

A retrospective review was conducted in a multicentre analysis over a one-year period from January 2019 to December 2019 at our institution. Computer tomography scans for foot and ankle injuries were reviewed, and posterior malleolus fractures were included. Pathoanatomical data was collected and analysed according to known classification systems and subsequent treatment modalities evaluated. A panel of observers individually reviewed radiographic data to determine interobserver reliability.

A total of 71 patients were included with a mean age of 41 ± 13.4 years (range 18-78) and a female predominant population (69%). A greater proportion of injuries were high energy (23.9%), with significant fragment comminution (53.5%), and half (52.1%) of all injuries were subluxated/dislocated at presentation. A total of 93% of injuries were managed operatively, despite theatre access limitations resulting in significant delays to fixation (19.1 days). Despite good pathoanatomical agreement with most international classifications, interobserver reliability was poor (Krippendorff α-coefficient < 0.667). Inconsistent treatment patterns in operative and non-operative strategies are reported.

A unique patient population of younger, female individuals incurred posterior malleolar fractures due to higher energy mechanisms of injury. Whilst injury patterns were mostly comparable, significant interobserver variability was noted. Resource limitations, diagnostic challenges, poorly defined and inconsistent treatment strategies, inevitably impact outcomes within the South African population.

Level III.

Ankle fractures are common lesions of the lower limbs. Approximately 40% of ankle fractures affect the posterior malleolus (PM). Historically, PM osteosynthesis was recommended when PM size in X-ray images was greater than 25% of the joint. Currently, computed tomography (CT) has been gaining traction in the preoperative evaluation of ankle fractures.

To elucidate the similarity in dimensions and to correlate PM size in X-ray images with the articular surface of the affected tibial plafond in the axial view on CT (AXCT) of a PM fracture.

Eighty-one patients (mean age: 39.4 ± 13.5 years) were evaluated (54.3% were male). Two independent examiners measured PM size in profile X-ray images (PMXR) and sagittal CT (SAGCT) slices. The correlation of the measurements between the examiners and the difference in the PM fragment sizes between the two images were compared. Next, the PM size in PMXR was compared with the surface of the tibial plafond involved in the fracture in AXCT according to the Haraguchi classification.

The correlation rates between the examiners were 0.93 and 0.94 for PMXR and SAGCT, respectively (P < 0.001). Fragments were 2.12% larger in SAGCT than in PMXR (P = 0.018). In PMXR, there were 56 cases < 25% and 25 cases ≥ 25%. When PMXR was < 25%, AXCT corresponded to 10.13% of the tibial plafond. When PMXR was ≥ 25%, AXCT was 24.52% (P < 0.001). According to the Haraguchi classification, fracture types I and II had similar PMXR measurements that were greater than those of type III. When analyzing AXCT, a significant difference was found between the three types, with II > I > III (P < 0.001).

PM fractures show different sizes using X-ray or CT images. CT showed a larger PM in the sagittal plane and allowed the visualization of the real dimensions of the tibial plafond surface.

Posterior malleolus fractures are known to be associated with ankle instability. The complexities involved in obtaining precise laboratory-based spatial pressure measurements of the ankle highlight the significance of exploring the biomechanical implications of these fractures.

Finite element analysis was utilized to examine the stress distribution across the contact surface of the ankle joint, both in its natural state and under varied sagittal fracture line angles. The study aimed to identify stress concentration zones and understand the influence of sagittal angles on stress distribution.

Three distinct stress concentration zones were identified on the ankle's contact surface: the anterolateral tibia, the anteromedial tibia, and the fracture line. The most significant stress was observed at the fracture line when a fracture occurs. Stress at the fracture line notably spikes as the sagittal angle decreases, which can potentially compromise ankle stability. Larger sagittal angles exhibited only minor stress variations at the contact surface's three vertices. It was inferred that sagittal angles below 60° might pose risks to ankle stability.

The research underscores the potential implications of fractures on the stress profile of the ankle joint, emphasizing the role of the contact surface in ensuring stability. The identification of three zones of stress concentration and the influence of sagittal angles on stress distribution offers a valuable reference for therapeutic decision-making. Further, the study reinforces the importance of evaluating sagittal fracture angles, suggesting that angles below 60° may compromise ankle stability.

Over the past decade, there has been a growing interest in the identification and treatment of posterior malleolus fragments, driven by a better understanding of their significance. The Mason & Molloy (M&M) classification system has emerged as a valuable tool for systematically categorizing these fractures and assisting clinicians in formulating treatment. We aim to assess the interobserver reliability of the M&M classification for posterior malleolus fracture by using 20 raters.

The study was conducted at a major foot and ankle referral center in Wythenshawe, Manchester, UK. Thirty-eight Computed Tomography (CT) scans were evaluated by 20 independent raters: 15 general orthopedic and trauma surgeons plus five foot and ankle surgeons. Each rater classified the posterior malleolus fracture according to M&M classification into type 1, 2A, 2B, 3, or not classifiable. Statistical analysis was done with the R software package and SPSS (v26; IBM Corp., Armonk, NY). Fleiss kappa (κ) coefficient with a 95% confidence interval (CI) was applied.

The interobserver agreement was moderate with a global κ value of 0.531 (95% CI: 0.518, 0.544). There were good agreements for identifying type 3 M&M (κ=0.785) and those that are not applicable for M&M classification (κ=0.785). There was a strong correlation between all raters in using M&M classification (Tb=0.53-0.59) except for Rater 12.

M&M classification remains a valuable tool to guide the management of patients with these subsets of ankle fractures.

The aim of the study was to evaluate the safety of the modified posteromedial approach (MfPM) in the surgical management of complex ankle fractures in terms of local complications.

Retrospective multicenter review of a series of malleolar fractures surgically treated by posterior ankle approaches between 2016 and 2022. Two approaches were used. In the MfPM group patients were placed in a prone position and the incision was made 1 cm medially to the Achilles tendon. In the posterolateral access (PL) group patients were placed in a prone or lateral decubitus position and the incision was made between the lateral malleolus and the Achilles tendon. Complications evaluated were divided into wound complications, infections, neuritis, vascular alterations and others.

81 ankle fractures with a posterior malleolar fragment treated by open reduction and internal fixation were identified. 20 cases were approached through the MfPM approach and 61 through the PL access. The mean follow up was 18.60 months (range 4-78 months). In the MfPM group the local complication rate was 10% (2/10 patients), both corresponding to minor wound problems which required no surgical intervention. No infection or other neural or vascular complications were found. In the PL group a complication rate of 8,19% (5/61 patients) was found, all of them corresponding to minor wound problems which required no surgical intervention. No infection or other neural or vascular complications were found. There were no significant differences between the two approaches regarding postoperative local complications (z score 0.249 - P: 0.803).

The MfPM approach is safe and may become as readily used as the PL due to the low incidence of postoperative local complications, especially in fractures with a large fragment and posteromedial extension in which greater access to the posterior pilon can facilitate instrumentation for anatomic reduction and fixation.

The aim of the study was to propose a classification system of posterior malleolar fractures by fracture lines with the use of CT scans, including 3D CT reconstruction, which can better understand morphological characteristics, analyze the mechanism and guide the surgeon to choose the optimal approach and fixation.

Patients with OTA/AO type 44 fractures involving the posterior malleolus and preoperative CT scans were included. We retrospectively analyzed 128 consecutive patients with posterior malleolar fractures from January 2013 to December 2019 at our institution. CT data were loaded into Mimics software (V20.0, Materialize), in which 3D CT reconstruction, morphological analysis and data measurements were made.

Based on the number of fracture lines in 128 consecutive patients, posterior malleolar fractures were classified into three types: type 1 with a single fracture line, type 2 with double fracture lines and type 3 with multiple fracture lines. According to the distribution of the fracture line, type 1 was divided into types 1A, 1B and 1C, and type 2 was divided into types 2A, 2B and 2C. The fracture line from the fibular notch to the posterior rim of the distal tibia was defined as type 1A, and the fracture line to the medial malleolus was defined as type 1B. Type 1C was a small fragment in the posterior rim of the distal tibia. Type 2A was regarded as type 1A with type 1C. It was considered type 2B because another fracture line started from the fracture line of type 1A and extended to the medial malleolus. In type 2C, we could see that the double fracture lines were all from the fibular notch to the posterior rim of the distal tibia and did not cross. Type 3 fractures were comminuted fractures with multiple fracture lines.

The morphology of posterior malleolar fractures, involvement of the fibular notch, or the medial malleolus can be obviously assessed by our classification system. We found the relation of the injury mechanism between type 1 and type 2 by comparing the area of the fragment. We have indicated that each type of fracture corresponds to its associated injury mechanism and which surgical approach and fixation can be chosen.

Surgical intervention is not typically used to treat symptoms after mild tibiofibular ligament injuries without ankle dislocation or subluxation.

To describe outcomes in patients arthroscopically treated for unique intra-articular lesions after sustaining syndesmosis injury of the ankle.

Case series; Level of evidence, 4.

A total of 11 elite male rugby players with a mean age of 21.0 years (range, 17-28 years) were referred to our hospital for prolonged posterior ankle pain after a high ankle sprain during rugby football. The patients were examined using standing view radiography, computed tomography (CT) and magnetic resonance imaging (MRI) to determine the extent of ligament damage. Posterior ankle arthroscopy was performed to examine intra-articular lesions. The patients were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle/hindfoot rating scale and sports activity score of the Self-Administered Foot Evaluation Questionnaire (SAFE-Q).

The average reduced tibiofibular overlap on the standing mortise view was 1.2 mm (range, 0.5-2.0 mm) compared with the opposite ankles. Mason type 1 fracture was detected on CT in 6 patients, and ossification of the interosseous membrane was detected in 2 patients. A bone bruise in the posterior malleolus was observed on MRI in all but 1 patient. Intra-articular fragments located in the posterior ankle were observed and removed arthroscopically. Symptoms improved rapidly after arthroscopic treatment in all patients. All patients returned to rugby games at a median of 11 weeks postoperatively. The median AOFAS scores improved from 77 preoperatively to 100 postoperatively (P < .01), and the median SAFE-Q sports activity subscale score improved from 49.4 to 100 (P < .01).

All unique intra-articular lesions that developed in rugby football players after syndesmosis injury were able to be treated arthroscopically. Patients returned to playing rugby football without syndesmosis reduction. Posterior ankle arthroscopy was effective in patients with residual symptoms after syndesmosis injury.