Evaluation of posterior malleolar fractures and the posterior pilon variant in operatively treated ankle fractures

A systematic review of posterior pilon variant fractures

Posterior pilon variant ankle fractures (PPVF) are a unique subtype of posterior malleolar fractures which have been a source of controversy and confusion in recent years. There has not been a thorough literature review previously written on the topic. Database searches of PubMed and Embase were conducted from inception until June 2023. The key words included "pilon variant," "posterior pilon variant," and "posterior pilon" fractures. Outcomes were evaluated by union time, rates of delayed union, nonunion, malunion, and complication. A total of 15 articles relevant to surgical repair of pilon variant fractures were included in the literature review. The unique mechanism of injury has been reported to involve both rotational and axial forces, leading to involvement of the posterior and medial aspects of the distal tibia. Pilon variant fractures can be suspected by several characteristics on radiographs and have a high confirmation rate via CT images. Multiple systems have been proposed to classify this fracture pattern, but there is no consensus on the ideal classification system. Surgically, direct fixation has shown better short-term clinical outcomes versus indirect fixation or no fixation. PPVF have a distinct fracture pattern involving the posterior and medial columns of the distal tibial plafond, and results from a mechanism intermediate to rotational and axial forces. These fractures are more severe than tri-malleolar fractures due to increased rates of articular impaction and incongruity. Future classification systems should focus on joint surface area and the tibial pilon column involved to avoid confusion with less severe posterior malleolar fractures.

Current Concepts in Ankle Fracture Management

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.

Combined vertical and external rotational force in plantarflexion position produces posterior pilon fracture: A preliminary cadaveric study

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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

Electric scooter injuries: Incidence and injury patterns at a level I trauma center

PURPOSE

Electric scooters (e-scooters) have become an increasingly popular mode of public transportation in recent years. As the incidence of related injuries rises, it is important to understand specific fracture patterns unique to e-scooters and electric bikes (e-bikes) to help guide management. The purpose of this study was to review the prevalence and describe specific fracture patterns of e-scooter and e-bike related injuries at the busiest level 1 trauma center in the borough of Manhattan.

METHODS

Chart review to determine mechanism of injury was performed on all patients for whom an orthopedic consult was requested from 1/1/2021 to 12/31/2021. All patients whose injuries were sustained due to an e-scooter or e-bike were further reviewed for demographics, injury characteristics including fracture pattern, and definitive injury management. Any patients who had an orthopedic consult placed for a reason other than an acute injury were excluded. Descriptive statistics are reported as frequency (percentage) for categorical variables and means for continuous variables.

RESULTS

Of the 1815 orthopedic consults requested, 1357 (74.8%) were for acute injury management. Of those with acute injuries, 119 (8.8%) sustained 136 e-scooter or e-bike related injuries. There were 92 (77.3%) males at an average age of (33.8 ± 15.7) years. Approximately one-fifth of all patients presented in June 2021 (26, 21.8%). There was a 9.2% rate of open fractures. The 136 injuries were evenly split between the upper and lower extremities, with 57 (47.9%) upper extremity, 57 (47.9%) lower extremity injuries, and 5 (4.2%) concomitant upper and lower extremity injuries. The most common fracture patterns were ankle fractures (16, 11.7%), followed by tibial shaft (14, 10.2%), tibial plateau (13, 9.5%), and radial head fractures (11, 8.0%). There was a 33.3% incidence of associated posterior malleolar fractures in the spiral tibial shaft fractures, 31.0% of posterior malleolar involvement and 18.8% of isolated vertical medial malleolar fractures in the ankle fractures, and 61.5% of posterior comminution in the tibial plateau fractures.

CONCLUSION

E-scooter and e-bike related injuries have a high incidence of tibial shaft fractures, ankle fractures, tibial plateau fractures, and radial head fractures. There should be a high index of suspicion for posterior and medial involvement in lower extremity fractures sustained due to e-scooter or e-bikes. Identifying specific fracture patterns seen in e-scooter and e-bike related mechanisms will help guide management of these injuries.

Enhancing Consistency in Posterior Malleolus Fracture Classification: A Comprehensive Interobserver Reliability Study With 20 Raters Using the Mason & Molloy Classification

INTRODUCTION

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.

METHODOLOGY

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.

RESULTS

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.

CONCLUSION

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

The treatment of a malunited posterior pilon fracture with talar dislocation: A staged surgical treatment protocol

BACKGROUND

Malunited posterior pilon fractures with talus dislocation (mPPFtd) are rare and there are no appropriate treatment strategies. The purpose of this study was to introduce a stepped strategy featuring preliminary soft tissue management according to the Ilizarov principle and delayed open reduction and internal fixation (ORIF) through a modified posteromedial approach to overcome rigid soft tissue contracture.

METHOD

From February 2015 to August 2021, 12 selected patients with mPPFtd who were treated with the staged protocol (Group A) were retrospectively analysed. The clinical and radiographic outcomes were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the visual analogue scale (VAS) score, and the Burwell-Charnley score. Moreover, this case series was compared with some cases of fresh fracture (Group B) in patients that had the same baseline data from our previous study.

RESULTS

In Group A, the average length of time between the date of injury and the date of surgery was 4.8 ± 3.3 months. The average time to external fixator distraction, as the first-stage treatment, was 13.4 ± 1.0 days. In the second stage of ORIF, the posterosuperior dislocation of the talus was corrected with osteotomy and leverage manoeuvres. According to the Burwell-Charnley score system, the reduction quality was excellent in 9 cases and good in 3 cases. After a mean follow-up of 3.8 ± 2.1 years, there were no infections, wound healing problems, or nerve injuries in our cohort, and union was observed in all fractures without a loss of reduction. The baseline data of the two groups were not significantly different (p>0.05). The mean AOFAS score in Group A was 85.0 ± 10.5 and that in Group B was 95.4 ± 6.1 (p<0.05). The mean VAS score in Group A was 1.7 ± 1.4 and that in Group B was 0.7 ± 0.9 (p<0.05).

CONCLUSION

A staged surgical treatment strategy characterized by soft tissue management will improve the treatment of mPPFtd and produce satisfactory clinical outcomes.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Morphological analysis and classification of posterior malleolar fractures based on CT scans

OBJECTIVES

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Classifications of posterior malleolar fractures: a systematic literature review

INTRODUCTION

Complex ankle fractures frequently involve the posterior malleolus. Many classifications describing posterior malleolar fractures (PMF) exist. The aim of this study was to provide a systematic literature review to outline existing PMF classifications and estimate their accuracy.

METHODS

The databases PubMed and Scopus were searched without time limits. Only specific PMF classifications were included; general ankle and/or pilon fracture classifications were excluded. Selection and data extraction was performed by three independent observers. The systematic literature search was performed according to the current criteria of Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). The methodological quality of the included studies was quantified using the modified Coleman score.

RESULTS

A total of 110 studies with a total of 12.614 patients were included. Four main classifications were identified: Those describing the size of the posterior malleolar fracture (n = 66), Haraguchi (n = 44), Bartoníček/Rammelt (n = 21) and Mason (n = 12). The quality of the studies was moderate to good with a median Coleman-score of 43.5 (14-79) and a weighted median Coleman-score of 42.5 points. All classifications achieved a substantial to perfect score regarding the inter- and intraobserver reliability, with Mason scoring the lowest in comparison.

CONCLUSIONS

None of the reviewed PMF classifications has been able to establish itself decisively in the literature. Most of the classifications are insufficient in terms of a derivable treatment algorithm or a prognosis with regard to outcome. However, as the Bartoníček/Rammelt classification has the greatest potential due to its treatment algorithm, its reliability in combination with consistent predictive values, its usage in clinical practice and research appears advisable.

Morphological study of CT image of posterior pilon variant fracture and its possible clinical significance

OBJECTIVE

The incidence of posterior pilon variant fractures has been underestimated. The purpose was to study the characteristics of posteromedial (PM) and posterolateral (PL) fragments in CT imaging of posterior pilon variant fractures, and to provide help for clinical diagnosis and treatment.

METHODS

CT imaging data of 109 cases of posterior pilon variant fractures in our hospital from January 2013 to December 2020 were retrospectively analyzed. According to Mason and Molloy classification, PM fragments were further divided into pilon subtypes and avulsed subtypes. The largest actual area of fragments in axial and sagittal were selected as the study plane, and the maximum axial lengths of X, Y and Z, α angle, β angle, fragment area (S1-7) and fragment area ratio (FAR1-4), interfragmentary (IF) angle, and back of tibia (BT) angle were measured.

RESULTS

A total of 109 cases were included in this study, 61 of whom were pilon subtypes [90.16% were supination-external rotation (SER) injuries]. 48 cases were avulsed subtypes [81.25% were pronation-external rotation (PER) injuries]. Pilon subtypes were larger than avulsed subtypes in X, Y, Z, α₂ Angle, β₂ Angle, fragment area and ratio, and IF and BT angle (P < 0.05). There was no difference between α₁ and β₁ angle (P > 0.05).

CONCLUSION

The morphology of pilon subtype was larger than that of avulsion subtype. According to fragment size, morphology, and injury mechanism, two fragments of pilon subtype should be anatomic reduction and fixation. However, the PL fragment of avulsion subtype should to be fixed, while PM fragment may only need conservative treatment.

Difference in Joint Stability Between Small Posterior Malleolar Fragments With Fixation and Those Without Fixation: A Biomechanical Cadaver Study

The indication for the surgical treatment of ankle fractures that involve a posterior malleolar fragment remains controversial. This cadaver study assessed the biomechanical results of rotation stiffness of Haraguchi type 1 posterior malleolar fragments with or without cannulated screw fixation. Twelve anatomic lower-extremity specimens from 6 cadavers were tested. Six right legs were subjected to posterior malleolus osteotomy (Haraguchi type I) followed with (group A; n = 3) or without (group B; n = 3) fixation using a cannulated screw. Ankle joint stability was measured under both external rotation force and axial loading, and the passive resistive torque was measured in both groups. The mean torque value in group A was 0.1093 Nm/º, while that in group B was 0.0537 Nm/º. There was a significant intergroup difference (p = .004). In group B, the torque value was further increased in the latter rotation period (about 40-60 degrees). Group A proved more stable under experimental conditions than group B. Fixation in type I posterior malleolar fragments produced improved stability in ankle rotation, even for posterior malleolar fragments involving <25% of the articular surface, and has been considered an effective aid in treatment.

Open reduction and internal fixation for posterior pilon fracture: Transfibular approach versus posterior approach

BACKGROUND

For posterior pilon fractures, the posterior approach (PA) is widely used but has its limitations. The transfibular approach (TFA) has been adopted to treat posterior malleolar fractures for the advantage of direct visual confirmation of the reduction status intraoperatively, yet the report of its application on posterior pilon fractures is rare. This study aims to compare TFA with PA in terms of their corresponding reduction quality.

METHODS

Clinical data of 85 posterior pilon fracture patients treated via PA (n = 62) or TFA (n = 23) were retrospectively reviewed. Radiographic and clinical assessments, including articular step-off or gap, syndesmosis reduction quality, signs of ankle arthritis, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, visual analogue scale (VAS), ankle stability, and the active range of motion (ROM) of the ankle, were all evaluated by two readers independently.

RESULTS

The total incidence of step-off or gap ≥ 1 mm was significantly higher in the PA group (35.5%) than in the TFA group (8.7%, p = 0.015). In all the patients, step-off ≥ 1 mm was identified as an independent risk factor for the development of arthritis and a lower AOFAS score (p < 0.001). No significant difference was found in ROM and complication incidence between the two groups. Ankle instability was found in neither group during the follow-up.

CONCLUSION

TFA could offer a way to intraoperatively evaluate the reduction status with direct visual confirmation and, thereby, might improve the results of reduction for posterior pilon fractures.

LEVEL OF EVIDENCE

Level III.

Posterior Malleolar Fracture Assessment: An Independent Interobserver and Intraobserver Validation of Three Computed Tomography-Based Classifications

BACKGROUND

Posterior malleolus fractures occur in up to 50% of all ankle fractures. Several classification systems exist for their characterization, especially under CT. However, those classifications do not report the level of agreement or do it incompletely. This study aims to independently assess three posterior malleolus fracture classifications (Haraguchi, Bartoníček/Rammelt, and Mason).

METHODS

This study was designed according to the Guidelines for Reporting Reliability and Agreement Studies. Ninety-four CT scans of patients with ankle fractures that had posterior malleolus fractures were included. Posterior malleolus fractures were assessed by six evaluators (three attending foot and ankle surgeons and three orthopaedic surgery residents) according to Haraguchi, Bartoníček/Rammelt, and Mason classifications. All images were reassessed by the same evaluators in a random sequence 3 weeks later. The kappa (k) coefficient was used to determine the interobserver and intraobserver agreement. Statistical significance was established using P < 0.05 with a 95% confidence interval (CI).

RESULTS

The interobserver agreement was moderate for Haraguchi, Bartoníček/Rammelt, and Mason classifications with a global k value of 0.52 (95% CI, 0.43 to 0.60), 0.53 (95% CI, 0.46 to 0.61), and 0.54 (95% CI, 0.47 to 0.62), respectively. The intraobserver agreement was substantial for Haraguchi, Bartoníček/Rammelt, and Mason classifications, with an overall k value of 0.70 (95% CI, 0.64 to 0.74), 0.73 (95% CI, 0.68 to 0.78), and 0.73 (95% CI, 0.69 to 0.78), respectively. Interobserver and intraobserver agreement among orthopaedic surgeons and residents had no significant difference.

CONCLUSION

The current classifications for posterior malleolus fractures showed a substantial intraobserver agreement. Nevertheless, the interobserver agreement obtained was just moderate for all classifications, independent of the level of expertise of the evaluators.

Treatment outcomes of posterior pilon fractures using a simple single lateral approach via stretching fibular fracture line

Purpose

The aim of this study was to explore the treatment outcomes of a novel single lateral approach via fibular fracture line for patients with posterior pilon fractures.

Patients and methods

From January 2020 to December 2021, a total of 41 patients with posterior pilon fractures who received surgical treatment in our hospital were retrospectively reviewed. Twenty patients (Group A) were treated with open reduction and internal fixation (ORIF) via posterolateral approach. Twenty-one patients (Group B) were treated with ORIF using a simple single lateral approach via stretching fibular fracture line. Clinical assessments, including operation time, intraoperative blood loss, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, visual analogue scale (VAS), and the active range of motion (ROM) of the ankle at the final follow-up visit after surgery, were performed in all patients. Radiographic outcome was evaluated by using the criteria proposed by Burwell and Charnley.

Results

The mean follow-up time was 21 months (range 12-35). The average operation time and intraoperative blood loss in the Group B were significantly less than those in the Group A. Moreover, the AOFAS score and ankle ROM in the Group B were significantly higher than those in the Group A at the final follow-up visit. Eighteen cases (90%) in Group A and 19 cases (90.5%) in Group B achieved anatomical reduction of the fracture.

Conclusion

The single lateral approach via stretching fibular fracture line is a simple and effective technique for reduction and fixation of posterior pilon fractures.

Comparison of prone-supine versus supine position for the treatment of pilon fractures via modified posteromedial approach combined with anterolateral approach

BACKGROUND

Most of modified posteromedial approaches require prone position for the treatment of pilon fractures. We describe the technique of modified posteromedial approach under supine position. The goal of the study was to compare the radiographic and clinical outcomes of prone-supine versus supine position for the treatment of pilon fractures via modified posteromedial approach combined with anterolateral approach.

METHODS

A total of 50 retrospectively consecutive pilon fractures that underwent open reduction internal fixation via modified posteromedial approach combined with anterolateral approach from 2016 to 2019 were reviewed at least a two-year follow up. The positions of patients were divided into two groups: prone-supine versus supine position (26 vs 24, respectively). The operation time, radiographic outcomes including bone union time and ratio of congruent articular reduction were evaluated. The post-operative function was evaluated using the Manchester Oxford score (MOXFQ) and the visual analogue score (VAS). The motion of ankle joint and complications and were also compared.

RESULTS

The mean follow-up was 42.2(24.7-73.0) months in the prone-supine group and 42.7(37.3-56.5) months in the supine group (P = .87). The mean operation time was 141.9 ± 10.1 min in the prone-supine group and 107.5 ± 18.9 min in the supine group (P = .00). There was no significant difference in the bone union time and ratio of congruent articular reduction between the two groups. There was no significant difference in the final MOXFQ score, VAS score, and the mean range of ankle motion between the two groups (P > .05). The total incidence of complications was 11.5% in the prone-supine group and 16.6% in the supine group (P = .66).

CONCLUSION

The patient in the prone-supine position versus supine position for pilon fractures via modified posteromedial approach combined with anterolateral approach contributed comparable quality of reduction, bone union time functional outcomes and complications. The supine technique was significantly shorter in terms of operation time.

Computed tomography-based classifications of posterior malleolar fractures and their inter- and intraobserver reliability: a comparison of the Haraguchi, Bartoníček/Rammelt, and Mason classifications

INTRODUCTION

Complex ankle fractures often include fractures of the posterior malleolus. The most clinically relevant posterior malleolus fracture classifications are computed tomography (CT) based. These classifications aim to enable clear communication and help develop treatment strategies. This study investigates the inter- and intraobserver reliability of the Haraguchi, Bartoníček/Rammelt and Mason posterior malleolar fracture classifications.

MATERIALS AND METHODS

CT scans of 113 patients with a mean age of 56.2 (SD ± 17.8) years and fractures involving the posterior malleolus were analyzed twice by 4 observers with different levels of training. The posterior malleolar fractures were classified according to Haraguchi et al., Bartoníček/Rammelt et al. and Mason et al. The intraobserver and interobserver reliabilities were determined by calculating Cohen's and Fleiss' kappa values.

RESULTS

We found substantial multi-rater interobserver agreement for all three classifications. The Haraguchi classification 0.799 (CI 0.744-0.855) showed the highest agreement, followed by the Bartoníček/Rammelt 0.744 (0.695-0.793) and Mason 0.717 (CI 0.666-0.768) classifications. Subgroup analyses showed substantial to perfect agreement for the Haraguchi and substantial agreement for the Bartoníček/Rammelt and Mason classifications independent of observer expertise. The intraobserver reliability was perfect for three and substantial for one of the observers. However, the classifications have certain pitfalls and do not consider the number of fragments, articular surface impressions, or intercalary fragments.

CONCLUSION

All classifications show substantial, if not perfect inter- and intraobserver reliabilities independent of observer level of expertise.

Temporizing cast immobilization is a safe alternative to external fixation in ankle fracture-dislocation while posterior malleolar fragment size predicts loss of reduction: a case control study

Background

To determine if temporizing cast immobilization is a safe alternative to external fixator (ex-fix) in ankle fracture-dislocations with delayed surgery or moderate soft-tissue injury, we analysed the early complications and re-dislocation rates of cast immobilization in relation to ex-fix in patients sustaining these injuries.

Methods

All skeletally mature patients with a closed ankle fracture-dislocation and a minimum 6-months follow-up treated between 2007 and 2017 were included. Baseline demographics, comorbidities, injury description, treatment history and complications were assessed.

Results

In 160 patients (94 female; mean age 50 years) with 162 ankle fracture-dislocations, 35 underwent primary ex-fix and 127 temporizing cast immobilizations. Loss of reduction (LOR) was observed in 25 cases (19.7%) and 19 (15.0%) were converted to ex-fix. The rate of surgical site infections (ex-fix: 11.1% vs cast: 4.6%) and skin necrosis (ex-fix: 7.4% vs cast: 6.5%) did not differ significantly between groups (p = 0.122 and p = 0.825). Temporizing cast immobilization led to an on average 2.7 days earlier definite surgery and 5.0 days shorter hospitalization when compared to ex-fix (p < 0.001). Posterior malleolus fragment (PMF) size predicted LOR with ≥ 22.5% being the threshold for critical PMF-size (p < 0.001).

Conclusion

Temporizing cast immobilization was a safe option for those ankle fracture-dislocations in which immediate definite treatment was not possible. Those temporized in a cast underwent definite fixation earlier than those with a fix-ex and had a complication rate no worse than the ex-fix patients. PMF-size was an important predictor for LOR. Primary ex-fix seems appropriate for those with ≥ 22.5% PMF-size.

Trial registration

The study does not meet the criteria of a prospective, clinical trial. There was no registration.

Operative strategy for tri-malleolar ankle fractures with posteromedial plafond involvement: a review of sixty six cases

PURPOSE

We aimed to summarize the radiographic and clinical outcomes in various conditions of tri-malleolar ankle fractures (TMFs) with posteromedial (PM) plafond involvement (TMF + PM) and determine the factors affecting their subjective clinical outcomes.

METHODS

Radiographic and clinical findings of 66 patients who underwent operative treatment for TMF + PM were retrospectively reviewed. The patients were classified into three groups according to the PM fracture line location. Type I fractures were defined when the PM fracture line extended medially beyond the PM corner of the distal tibia while type II fractures were those in which the PM fracture line was located laterally to the PM corner. Type III fractures were defined as medial malleolar avulsion fractures when the PM fracture integrated into the medial malleolus. Clinical outcomes were evaluated using a subjective rating scale (excellent, good, fair, poor, and bad). Satisfactory results were defined as excellent, good, and fair. Factors affecting satisfactory clinical outcomes were assessed using a binary logistic regression analysis. Independent variables included demographic, fracture-related, and operation-related factors and radiographic measurements at the final follow-up.

RESULTS

Satisfactory clinical outcomes were observed in 74.2% of the total patients; of these patients, 75.7% (28/37), 76.5% (13/17), and 66.7% (8/12) had type I, type II, and type III fractures, respectively. The binary logistic regression analysis revealed that age at the time of operation, number of incarcerated fragments (IFs), type of IFs, and postoperative articular step-offs (mm) were related to subjective clinical outcomes (all P < 0.05). A positive value for post-operative articular step-offs represented distal migration of the posterior malleolar fragments. The odds ratios for older age, increased numbers of IFs, rotated IFs, and positive articular step-offs were 0.936, 0.116, 0.020, and 0.295, respectively.

CONCLUSION

Because TMF + PM is highly unstable, a delicate approach is needed according to each patient's fracture condition. Although it is best to reduce the fractured articular surface, a negative step-off, rather than a positive step-off, would be more likely recommended if accurate reduction is impossible. This could be applied to manage IFs, especially when the IFs are rotated. Dimpling of the articular surface induced by the removal of a small IF was not related to unsatisfactory clinical outcomes.

Clinical Outcomes for Pilon Variant Posterior Malleolar Fractures: A Multicenter Retrospective Analysis

Currently, there is no consensus on surgical approach for posterior malleolar fracture fragments with significant posteromedial involvement. The Bartonicek type III/Haraguchi type II posterior malleolar morphologies typically involve large posteromedial fragments, behaving like a pilon injury and have been reported as pilon variant fractures. We performed a retrospective chart review at 2 large healthcare institutions, evaluating patients that underwent surgical management of pilon variant posterior malleolar fractures and determining clinical outcomes including: time to union, union rates, soft tissue complications, infection and time to weight bearing. A total of 68 patients were included (51 females, 17 males). A total of 51 direct (19 posterolateral, 31 posteromedial), 6 indirect, and 11 no-fixation approaches were identified. Significantly different time-to-union was found between direct fixation (mean = 85.1 days), indirect fixation (mean = 74 days) and no-fixation (mean = 174.3 days) (p < .001). A posteromedial approach (mean = 63.0 days, SD = 16.6) was associated with significantly shorter time to union when compared to a posterolateral approach (mean = 124.8 days, SD = 59.4; p < .001). Fixation (direct or indirect) was associated with significantly increased likelihood of union of the overall ankle fracture pattern (52/57 = 91%) when compared to no fixation of the posterior malleolar component (9/14 = 64%), p = .01. Patients who underwent direct fixation had significantly lower incidence of neurovascular damage (6%) when compared to patients who underwent indirect fixation (33%) or no-fixation (29%) (p = .02). There was no significant difference between the groups in terms of tendon damage (p = .54), infection rates (p = .45) and time to weight bearing (p = .66). The authors suggest that surgical management and specifically direct approaches have better outcomes in the short-term follow up.

Complications following surgical treatment of posterior malleolar fractures: an analysis of 300 cases

AIMS

The treatment of ankle fractures and fracture-dislocations involving the posterior malleolus (PM) has undergone considerable changes over the past decade. The aim of our study was to identify risk factors related to the occurrence of complications in surgically treated ankle fractures with PM involvement.

PATIENTS AND METHODS

We retrospectively analyzed 300 patients at a mean age of 57 years with 300 ankle fractures involving the PM treated surgically at our institution over a 12-year period. The following relevant comorbidities were noted: arterial hypertension (43.7%; n = 131), diabetes mellitus (DM) (14.0%; n = 42), thereof insulin-dependent (3.7%; n = 11), peripheral vascular disease (0.7%; n = 2), osteoporosis (12.0%; n = 36), dementia (1.0%; n = 3), and rheumatoid arthritis (2.0%; n = 6). Furthermore, nicotine consumption was recorded in 7.3% (n = 22) and alcohol abuse in 4.0% (n = 12).

RESULTS

Complications occurred in 41 patients (13.7%). A total of 20 (6.7%) revision surgeries had to be performed. Patients with DM (p < 0.001), peripheral vascular disease (p = 0.003) and arterial hypertension (p = 0.001) had a significantly increased risk of delayed wound healing. Alcohol abuse was associated with a significantly higher overall complication rate (OR 3.40; 95% CI 0.97-11.83; p = 0.043), increased rates of wound healing problems (OR 11.32; 95% CI 1.94-65.60; p = 0.001) and malalignment requiring revision (p = 0.033). The presence of an open fracture was associated with an increased rate of infection and wound necrosis requiring revision (OR 14.25; 95% CI 2.39-84.84; p < 0.001). Multivariate analysis identified BMI (p = 0.028), insulin-dependent DM (p = 0.003), and staged fixation (p = 0.043) as independent risk factors for delayed wound healing. Compared to the traditional lateral approach, using the posterolateral approach for fibular fixation did not lead to increased complication rates.

CONCLUSIONS

Significant risk factors for the occurrence of complications following PM fracture treatment were identified. An individually tailored treatment regimen that incorporates all risk factors is important for a good outcome.

Posterior pilon fracture treated by opening the fibula fracture gap

Background

Posterior pilon fracture is a relatively common clinical fracture involving the posterior articular surface of the distal tibia. Currently, this form of fracture is receiving increasing attention. The surgical approach and technique for the treatment of posterior pilon fractures are still controversial. The purpose of this retrospective study was to compare the clinical and imaging outcomes of pilon fractures after treatment with the open fibula fracture line (OFFL) surgical technique versus the traditional posterolateral approach (TPL).

Methods

A retrospective analysis of patients with posterior pilon fractures treated using the open fibula fracture line technique and the traditional posterolateral approach between January 2015 and March 2020. Thirty-one cases were included in the open fibula fracture line technique group and twenty-eight cases were included in the traditional posterolateral approach group. We used the Burwell-Charnley scale to assess the effectiveness of surgical repositioning. The clinical outcomes were evaluated using American Orthopaedic Foot & Ankle Society ankle-hind foot score (AOFAS) and visual analog score (VAS).

Results

The overall anatomic reduction rate was slightly better in the open fibula fracture line group than in the conventional posterolateral group (81% vs. 71%, p = 0.406), but there was no statistically significant difference between the two groups. There were no statistically significant differences between the two groups in terms of fracture healing time and time to full weight bearing (p > 0.05). At the final follow-up, the AOFAS functional score of the open fibula fracture line group was statistically superior to that of the conventional posterolateral group (p < 0.05). However, there was no statistical difference between the two groups in VAS pain scores at rest, during activity, and under weight bearing (p > 0.05).

Conclusion

The trans-fibular fracture approach provides a better surgical option for specific types of posterior pilon fractures with a high rate of anatomic repositioning and a good near-term outcome.

Trial registration: Retrospective registration.

Peroneal artery safe zone in the posterolateral approach to the distal tibia: A CT angiogram based anatomical study

OBJECTIVES

The posterolateral approach to the distal tibia is commonly used for stabilisation of ankle fractures as it allows good visualisation and direct reduction of the posterior distal tibia and malleolar fragments. This approach can also be used for internal fixation of an associated lateral malleolus fracture. The aim of our study is to describe the surgical anatomy of the peroneal artery (PA) in relation to the tibial plafond and the distal fibula; thereby suggesting a safe zone during proximal dissection of posterolateral approach.

METHODS

Using Computed Tomography Angiographic (CTA) study, the course of the PA in relation to the tibial plafond and distal fibula was analysed in 142 lower limbs (bilateral limbs of 71 adult patients; 43 males and 28 females). Axial, coronal, and sagittal CT sections were cross-linked to specify the position of the PA. The PA course was identified and the level of its distal bifurcation over the tibia was marked. Perpendicular measurements were made from this point to the tibial plafond and tip of distal fibula.

RESULTS

The PA bifurcated distally at mean 58.3±24.2mm (SD) (range: 37.0-115.0mm) proximal to the right tibial plafond and mean 81.9±24.4mm (range: 54.0-137.0mm) from the right distal fibular tip. In the contralateral side, the PA bifurcated at mean 57.9±23.3mm (range: 36.0-125.0mm) proximal to the left tibial plafond and 81.8±23.9mm (range: 54.0-147.0mm) from the left distal fibular tip. The difference between the right and the left side of distal bifurcation point diameter of the same patient was assessed, range (0.0-58.0mm) with median 2.0mm and IQR 10.0mm. Three different PA vasculature patterns were identified.

CONCLUSIONS

It is important for surgeons to be aware of the surgical anatomy of PA to avoid inadvertent injury during posterolateral approach to distal tibia. The PA may bifurcate as close as 36mm from the tibial plafond with possible variation bilaterally. Therefore, special attention needs to be considered by the operating surgeon while dissecting in this region due to the wide anatomical variation in vasculature. However, once the PA is mobilised, any fixation modality including posterior buttress plate could be safely performed.

Analysis of the efficacy of a modified posteromedial approach for Klammer III posterior Pilon fractures

PURPOSE

To analyze the curative effect and technical points of a modified posteromedial approach in the treatment of Klammer III posterior Pilon fracture.

METHODS

A retrospective analysis of patients with Klammer III posterior Pilon fractures were conducted in our department from January 2018 to December 2019. Before the surgery, the patients were fully relieved of swelling and pain, and a comprehensive examination was carried out. The posteromedial approach exposed the posterior and medial fracture block of the distal tibia. According to the fracture of external malleolus, it is determined whether to combine a lateral incision and protect tendons and vascular nerves by a retractor, and then perform a fracture reduction and internal fixation. Postoperatively, the patients were treated with analgesia, detumescence, anticoagulation and rehabilitation exercise. The American orthopaedic foot and ankle society (AOFAS) score and visual analogue score were recorded at regular follow-up after surgery. A t-test was used for the comparison of the preoperative and final AOFAS score.

RESULTS

There were 7 male and 13 female (n = 20) included in the study, aged 22 to 88 years (average age 54.2 years). The injury mechanisms were falling from a height (n = 7), traffic accident (n = 6), walking injury (n = 2) and heavy injury (n = 5). The postoperative follow-up duration was 12-24 months (mean 16.95 months). The AOFAS score of the 20 patients before and after surgery were compared. The preoperative AOFAS score was 38.90 ± 3.91, and the final AOFAS score was 80.55 ± 4.20, (p < 0.001). The mean final visual analogue scores at rest, active and weight-bearing walking were 0.30, 0.85 and 1.70, respectively. One patient reported poor postoperative wound healing and required a return to hospital for debridement and anti-infection treatment.

CONCLUSION

In the treatment of Klammer III posterior Pilon fractures, the modified posteromedial approach can fully expose the fracture block and the collapsed articular surface of the medial malleolus, achieve good reduction and internal fixation with limited injury of the tendon and vascular nerves, and have a better prognosis.

Ankle fractures involving the posterior malleolus: patient characteristics and 7-year results in 100 cases

INTRODUCTION

The presence of a posterior malleolar (PM) fragment has a negative prognostic impact in ankle fractures. The best treatment is still subject to debate. The aim of this study was to assess the medium-to-long-term clinical and functional outcome of ankle fractures with a PM fragment in a larger patient population.

MATERIALS AND METHODS

One hundred patients (69 women, 31 men, average age 60 years) with ankle fractures including the PM were evaluated clinically and radiographically. Patients with Bartoníček-Rammelt type 3 and 4 fracture displayed a significant female preponderance. Fixation of the PM was performed in 63% and tailored to the individual fracture pattern.

RESULTS

Internal fixation of the PM fragment was negatively correlated with the need for syndesmotic screw placement at the time of surgery (p = 0.010). At an average follow-up of 7.0 years, the mean Foot Function Index (FFI) was 16.5 (SD: 21.5), the Olerud Molander Ankle Score (OMAS) averaged 80.2 (SD: 24) and the American Orthopedic Foot & Ankle Society (AOFAS) ankle/hindfoot score averaged 87.5 (SD: 19.1). The maximum score of 100 was achieved by 44% of patients. The physical (PCS) and mental health component summary (MCS) scores of the SF-36 averaged 47.7 (SD: 12.51) and 50.5 (SD: 9.36), respectively. Range of motion was within 3.4 (SD: 6.63) degrees of the uninjured side. The size of the PM fragment had no prognostic value. There was a trend to lower outcome scores with slight anterior or posterior shift of the distal fibula within the tibial incisura. Patients who underwent primary internal fixation had significantly superior SF-36 MCS than patients who underwent staged internal fixation (p = 0.031).

CONCLUSIONS

With an individualized treatment protocol, tailored to the CT-based assessment of PM fractures, favorable medium and long-term results can be expected.

Simultaneous Posterolateral and Posteromedial Approaches for Fractures of the Entire Posterior Tibial Plafond: A Safe Technique for Effective Reduction and Fixation

OBJECTIVE

To determine the short-term results of surgical treatment with dual posterolateral and posteromedial approaches for fractures of the entire posterior tibial plafond and secondarily to identify common fracture characteristics.

DESIGN

Retrospective.

SETTING

Single academic Level 1 trauma center.

PATIENTS

Thirty-five patients with posterior pilon fractures followed until fracture union (minimum 3 months).

INTERVENTION

Surgical treatment using simultaneous combined posterolateral and posteromedial exposures for fracture reduction and internal fixation.

MAIN OUTCOME MEASUREMENT

(1) Surgical outcomes including rate of wound complications and accuracy of the articular reduction. (2) Fracture characteristics including the incidence of articular impaction, comminution interfering with reduction, syndesmosis injury, and the type of fibula fracture.

RESULTS

The rate of wound problems was low (6%), and 94% of patients had an articular reduction with less than 1 mm of step or gap. There were high rates of articular comminution (83%) and posteromedial articular impaction (63%) and a 17% rate of syndesmosis injury requiring repair.

CONCLUSIONS

Surgical fixation using simultaneous, combined posterolateral and posteromedial approaches for posterior pilon fractures had a low rate of wound complications and was an effective strategy for obtaining an accurate reduction. The rate of syndesmotic instability requiring fixation was lower than previous work reporting on fixation using a single approach. This may be a useful technique for surgeons who treat these injuries. Careful assessment of the preoperative imaging is required in patients with posterior pilon fractures.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Posterior Malleolar Fractures: A Critical Analysis Review

In patients with ankle fractures, the presence of a posterior malleolar fracture has a negative impact on the prognosis. Computed tomography (CT) scanning is essential for fracture classification and treatment planning, as the indication for surgery depends on the 3-dimensional fragment outline and displacement, incisura involvement, and the presence of joint impaction. Anatomic reduction of a posterior malleolar fragment restores the incisura, facilitating reduction of the distal part of the fibula, and it also restores the integrity of the posterior portion of the syndesmosis, reducing the need for additional syndesmotic stabilization. Direct open reduction and fixation of posterior malleolar fragments from a posterior orientation is biomechanically more stable and provides a more accurate reduction than does indirect reduction and anterior-to-posterior screw fixation. Intra-articular step-off of >=2 mm is an independent risk factor for an inferior outcome and the development of posttraumatic arthritis, irrespective of the fragment size.

Ankle Fracture with a Complex Injury Mechanism and Misleading Hook Test Result: A Case Report

Ankle fractures and their mechanisms of injury can be complex. We report a case of a patient with an uncertain mechanism of injury and an uncommon combination of lower extremity fractures, which fit the criteria for a Lauge-Hansen classification pronation-external-rotation fracture, Maisonneuve fracture, Wagstaffe fracture, and posterior pilon fracture. Plain radiographs and computed tomography scan revealed Chaput tubercle avulsion fractures, an anterior distal fibular fracture fragment, multiple lateral malleolar fractures, a posterior malleolar fracture fragment with proximal displacement, a die-punch fragment between the posterior malleolar fragment and the tibia, a proximal fibular fracture, and possible ankle syndesmotic diastasis. Intraoperative hook test was negative after fixation of the fractures, so syndesmotic fixation was not performed. At 3-month follow-up, plain radiographs showed obvious syndesmotic diastasis. At 1-year follow-up, symptoms persisted and syndesmotic fusion was recommended but declined by the patient. This case demonstrates that both ankle fractures and their mechanisms of injury can be remarkably complex and confusing, posterior pilon fractures can occur along with pronation-external-rotation ankle fractures, syndesmotic fixation should be considered for all patients with Maisonneuve fractures, reliance on the hook test for surgical management decisions may not always be reliable, and there exists a need for a more accurate and reliable intraoperative test to determine the presence of ankle syndesmotic injury.

ACR Appropriateness Criteria® Acute Trauma to the Ankle

Acute injuries to the ankle are frequently encountered in the setting of the emergency room, sport, and general practice. This ACR Appropriateness Criteria defines best practices for imaging evaluation for several variants of patients presenting with acute ankle trauma. The variants include scenarios when Ottawa Rules can be evaluated, when there are exclusionary criteria, when Ottawa Rules cannot be evaluated, as well as specific injuries. Clinical scenarios are followed by the imaging choices and their appropriateness with an accompanying narrative explanation to help physicians to order the most appropriate imaging test. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Comprehensive biomechanical analysis of three clinically used fixation constructs for posterior malleolar fractures using cadaveric and finite element analysis

Different fixation modalities are available for fixation of posterior malleolar fractures (PMFs), but the best method is still unclear. The purpose of this study was to carry out a comparative biomechanical analysis of three commonly used fixation constructs for PMFs using experimental and finite element analysis (FEA). 15 human cadaveric ankle specimens were randomly divided into three groups. Specimens in group-A were fixed with two anteroposterior (AP) lag screws, group-B with two posteroanterior (PA) lag screws, and for group-C, a posterior plate was used. Each model was subjected to axial load. Outcomes included loads for 0.5 mm, 1 mm, 1.5 mm, and 2 mm vertical displacements of posterior fragments were noted. 3D FE models were reconstructed from computed tomography (CT) images and subjected to vertical loads. The model’s stress, fracture step-off, and resultant strains in implants were also studied in 3D FE models. Significantly higher amounts of mean compressive loads were observed to cause the same amount of vertical displacements in plate group (265 ± 60.21 N, 796 ± 57.27 N, 901.18 ± 8.88 N, 977.26 ± 13.04 N) than AP (102.7 ± 16.78 N, 169.5 ± 19.91 N, 225.32 ± 15.92 N, 269.32 ± 17.29 N) and PA (199.88 ± 31.43 N, 362.80 ± 28.46 N, 431.3 ± 28.12 N, 541.86 ± 36.05 N) lag screws respectively (P < 0.05). Simulated micro-motion analysis demonstrated that fracture step-off values in plate group (0.03 ± 0.001 mm, 0.06 ± 0.003 mm and 0.13 ± 0.010 mm) were the lowest among the three groups (P < 0.001). The cancellous bone showed the highest amount of stress in AP and PA lag groups respectively, whereas the lowest stress was noted in the plate-group. This biomechanical study concluded that posterior plating is biomechanically the most stable fixation construct for PMFs fixation. AP and PA lag screws with higher bone stress and fracture step-off values have a high tendency of bone cut-through and loss of fixation respectively.

Combined Posteromedial and Posterolateral Approaches for 2-Part Posterior Malleolar Fracture Fixation

BACKGROUND

This study investigated the clinical efficacy of combined posteromedial and posterolateral approaches for repair of 2-part posterior malleolar fractures associated with medial and lateral malleolar fractures.

METHODS

This case series report included 27 Weber B with Haraguchi type II patients with medial and lateral malleolar fractures combined with 2-part posterior malleolar fractures. Patients were treated with open reduction and internal fixation through a combination of posteromedial and posterolateral approaches from January 2015 to January 2018. There were 11 males and 16 females, with an average age of 61.5 years (range, 53-67 years). The procedures were performed on prone patients under spinal anesthesia. The medial, lateral, and posterior malleolar fractures were exposed through posteromedial and posterolateral approaches performed at the same time. The lateral malleolar fracture was fixed using a plate, the medial malleolar fracture was fixed using screws, and the posterior malleolar fracture was fixed using a plate or cannulated screws according to the size of the fragments. We performed follow-up on 22 patients for an average of 30 months (range, 18-48 months).

RESULTS

Primary healing of the incisions was achieved in all cases, and no infection was found. The mean time of bone union was 12.5 weeks (range, 10-15 weeks). The mean time from the operation to full weightbearing was 13 weeks (range, 11-16 weeks). We used the American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot Scale to score patient outcomes; the mean score was 85.4 (range, 80-92) at the final follow-up. No significant pain was found at the final follow-up.

CONCLUSION

This study showed that satisfactory outcomes were achieved with combined posteromedial and posterolateral approaches. Therefore, we believe this approach was a good alternative strategy to repair 2-part posterior malleolar fractures associated with medial and lateral malleolar fractures.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Comparison of radiographs and CT features between posterior Pilon fracture and posterior malleolus fracture: a retrospective cohort study

OBJECTIVES

This study explored the morphological differences between posterior Pilon fracture and posterior malleolus fracture from radiographs and CT to provide detail for diagnosis and treatment of them.

METHODS

Radiographs and CT imaging data of 174 patients with distal posterior tibial fractures who were treated from January 2013 to January 2019 were retrospectively analyzed. Based on the operation and imaging examination, the fractures were classified into posterior Pilon fractures and posterior malleolus fractures. Radiographic parameters including the width, height, depth, α angle, β angle, γ angle, fragment area ratio 1 (FAR1), δ angle and fragment area ratio 2 (FAR2) of ankle mortise were measured.

RESULTS

There were 96 posterior Pilon fractures (Type I: 30, Type II: 22 and Type III: 44) and 78 posterior malleolus fractures (Type I: 40 and Type II: 38). The ankle depth, α angle, γ angle, FAR1 and FAR2 of posterior Pilon fractures were larger than these of posterior malleolus fractures (p < 0.05). In addition, FAR1 and FAR2 of Type II and Type III posterior Pilon fractures were significantly larger than these of Type I (p < 0.05). FAR1 and FAR2 of Type I posterior malleolus fractures were significantly smaller than these of Type II (p < 0.05).

CONCLUSION

Radiographs combined with CT analysis is an effective method to accurately distinguish morphological features between posterior Pilon fracture and posterior malleolus fracture.

ADVANCES IN KNOWLEDGE

Radiographs combined with CT distinguished the fracture of posterior malleolus and posterior Pilon rapidly and accurately, instead of operation.

Open Reduction and Internal Fixation of Posterior Malleolus Fractures via a Posteromedial Approach

Ankle fractures with a posterior malleolus component are complex injuries. The most commonly used operative methods include indirect reduction via a percutaneous anterior approach and direct reduction via a posterolateral approach. For large posterior malleolus fractures with medial extension, direct reduction via a posteromedial approach is an alternative operative option. The authors hypothesized that fixation of large posterior malleolus fractures via a posteromedial approach results in anatomic reduction and stable plate fixation. From 2008 to 2015, 22 (9.0%) of 244 consecutive operative ankle fractures were identified as posterior malleolus fractures treated using a posteromedial approach. Patient charts were retrospectively reviewed for demographics, operative details, follow-up time, and any postoperative complications. Postoperative radiographs were reviewed to ensure that anatomic reduction and stable fixation was maintained. Sixteen (72.7%) of 22 patients were female, and the average age at the time of surgery was 54.1 years (range, 26-86 years). The average follow-up time was 13.0 months (range, 2.0-41.4 months). Twenty-one (95.5%) of 22 patients healed on a radiographic and clinical basis. There was an 18.2% (4 of 22) postoperative complication rate: 1 patient had a nonunion, 1 patient had cellulitis, 1 patient had osteomyelitis involving the fibula, and 1 patient had symptomatic heterotopic ossification. Open reduction and internal fixation of posterior malleolus fractures via a posteromedial approach achieved anatomic reduction, stable plate fixation, and complete healing in all but 1 patient. This study demonstrates that the posteromedial approach is a reasonable alternative to other more commonly used methods for treating these fractures. [Orthopedics. 2020;43(3):e166-e170.].

Mechanism of posterior malleolar fracture of the ankle: A cadaveric study

Objectives:

Ankle fracture treatment involves reduction of the bone fragments and stabilization of the joint by reversing the mechanics of injury. For posterior malleolar fracture however, the true mechanism is not understood, leading to a lack of consistent guidance on how to best treat this injury.

Methods:

Fifteen cadaver ankles were subjected to fracture loading that replicated the Lauge-Hansen pronation-external rotation mechanism. An axial load was applied to each specimen, which was mounted on a materials testing machine, and the foot was rotated externally to failure. Digital video cameras recorded the failure sequence of specific anatomic structures.

Results:

Posterior malleolar fracture occurred in 7 specimens. Of these, 1 was an intra-articular fracture, another was a fracture involving the entire posterior tibial margin consisting of 2 fragments: that of the posterior tubercle and that of the posteromedial margin of the tibial plafond, with the former judged to be a consequence of avulsion by the posterior inferior tibiofibular ligament and the latter a consequence of axial loading from the talus. In the remaining 5 specimens, the posterior malleolar fracture was a small extra-articular avulsion fracture.

Conclusions:

Fractures at the posterolateral corner of the distal tibia were shown to be avulsion fractures attributed to the posterior inferior tibiofibular ligament and produced by external rotation of the talus. A fracture involving the entire posterior tibial margin consisting of 2 fragments can be produced by a combination of avulsion by the posterior inferior tibiofibular ligament and axial loading from the talus.

Anatomy, Classification, and Management of Ankle Fractures Involving the Posterior Malleolar Fragment: A Literature Review

The posterior malleolar fragment is frequently involved in rotational ankle fractures, but diagnosis and definitive management remains controversial. Ankle fractures with a posterior malleolar component that are not identified and treated in a timely manner may contribute significantly to future comorbidities, including continued pain, instability, and the development of arthritis. This article highlights the anatomic features of posterior malleolar ankle fractures, the classification schemes used, and discusses the various nonsurgical and surgical methods currently used.

Posterior pilon fracture: Epidemiology and surgical technique

OBJECTIVES

To review a case series of patients with posterior pilon variant fracture using a novel approach, focusing on demographic data, injury pattern, surgical results based on computed tomography (CT) scan, and short-term complications.

DESIGN

Consecutive case series.

SETTING

Level I trauma center.

PATIENTS/PARTICIPANTS

Twenty-five patients with posterior pilon fracture.

INTERVENTION

Posterior pilon fracture open reduction and internal fixation.

MAIN OUTCOME MEASUREMENTS

Parameters measured included age, sex, type of fracture, surgical technique, anatomical reduction, and complications.

RESULTS

Twenty-five patients sustained a posterior pilon fracture, accounting for 13.4% of all operatively treated ankle fractures with median follow-up of 21.7 months. The average age of patients was 42 years (22-62); 19/25 (76%) were female, and 6/25 (24%) were male. A modified posteromedial approach was used in 18/25 (72%) patients. Persistent syndesmotic instability was present in 11/25 (44%) patients after posterior malleolar stabilization. Quality of reduction was assessed under CT scan in 19 patients, with 15/19 (78.9%) having anatomic reduction. We report 2/25 (8%) patients with early wound problems and 7/25 (20%) with short-term complications during follow-up.

CONCLUSION

Posterior pilon variant fracture appears to be less common than previously reported. Most fractures can be satisfactorily treated through a modified posteromedial approach. Albeit obtaining posterior malleolar fracture rigid fixation, syndesmotic instability was more prevalent than expected. The short-term complication rate was low.

LEVEL OF EVIDENCE

Therapeutic level IV.

Advances in the Surgical Management of Ankle Fractures

Ankle fractures are one of the most common injuries treated by orthopedic surgeons worldwide. However, operative indications, techniques, and reported outcomes following operative fixation vary widely in the literature. This evidence-based review focuses on recent advances in the operative management of ankle fractures including arthroscopic-assisted surgery, deltoid ligament complex repair, expanded indications for posterior malleolus fixation, fibula intramedullary nailing, and dynamic syndesmosis repair.

LEVEL OF EVIDENCE

Level V, expert opinion.

Clinical Outcomes of Hyperplantarflexion Variant Compared With Supination External Rotation Ankle Fractures: A Matched-Cohort Analysis

Recent literature has reported an uncategorized hyperplantarflexion variant ankle fracture characterized by a posteromedial fragment separate from the posterior or medial malleolar fragments. The current study sought to determine whether the outcomes for surgically treated hyperplantarflexion variant fractures are similar to the more common supination external rotation (SER) IV fractures. A prospective registry of operatively treated ankle fractures was queried to create 2 age- and gender-matched cohorts: hyperplantarflexion variant and SER IV fractures. Each cohort had 23 patients (18 females), and matched pairs were within 2 years of age at the date of surgery. Patient demographics, comorbidities, and Foot and Ankle Outcomes Scores at minimum 12 months after the index surgery were compared. The cohorts were similar with respect to body mass index, the length of the clinical follow-up, medical comorbidities, dislocation rate, and postoperative articular incongruity (p > .05). Patient-reported outcomes demonstrated no statistically or clinically significant differences within any domain and were as follows: symptoms (70.8 versus 77.8, p = .11), pain (80.7 versus 85.0, p = .33), activities of daily living (83.7 versus 89.2, p = .23), sports (67.4 versus 73.4, p = .33), and quality of life (57.3 versus 63.9, p = .24) for the hyperplantarflexion and SER IV groups, respectively. No significant differences were found in the rang`e of motion for dorsiflexion (17.7° versus 18.1°, p = .52) or for plantarflexion (48.6° versus 47.1°, p = .71). Patients treated surgically for hyperplantarflexion variant ankle fractures have similar 1-year clinical outcomes when compared with the more common SER IV fracture patterns, provided that the injury is correctly identified preoperatively and treated appropriately.

Treatment outcomes of the posterolateral approach of plate fixation for posterior pilon fractures

Posterior pilon fracture is a common type of intraarticular fracture encountered in clinical practice. The treatment of this fracture pattern has been increasingly reported. However, methods for minimizing the associated surgical trauma and achieve effective fixation still require to be established. The present study involved 23 patients with posterior pilon fracture treated at the First Affiliated Hospital of Soochow University (Suzhou, China) between March 2013 and October 2017. Klammer's classification system was used to divide the posterior pilon fractures into 3 types. The surgical procedure, reduction of post-operative fracture, peri-operative complications and post-operative functional recovery were reviewed and analyzed. The reduction in post-operative fractures was evaluated by determining the Burwell-Charnley scores at the last follow-up. Anatomical reduction was confirmed in 17 patients, and an acceptable reduction was reported in 6 patients. The American Orthopedic Foot and Ankle Score was used to assess ankle function recovery; the average score was 82.3 points (range, 44-97 points). In conclusion, the posterolateral approach is able to achieve anatomical exposure of the operative field. In addition, the posterior fracture fragment of the tibia may be fully exposed through the fibula fracture gap by retraction. Posterior placement of the plate may serve a definitive role in the fixation of the posterior fracture fragment and maintain stability in the anatomical reduction of the fracture, which is helpful in early functional rehabilitation.

Morphological characteristics of the posterior malleolar fragment according to ankle fracture patterns: a computed tomography-based study

Background

The posterior malleolar fragment (PMF) of an ankle fracture can have various shapes depending on the injury mechanism. The purpose of this study was to evaluate the morphological characteristics of the PMF according to the ankle fracture pattern described in the Lauge-Hansen classification by using computed tomography (CT) images.

Methods

We retrospectively analyzed CT data of 107 patients (107 ankles) who underwent surgery for trimalleolar fracture from January 2012 to December 2014. The patients were divided into two groups: 76 ankles in the supination-external rotation (SER) stage IV group and 31 ankles in the pronation-external rotation (PER) stage IV group. The PMF type of the two groups was assessed using the Haraguchi and Jan Bartonicek classification. The cross angle (α), fragment length ratio (FLR), fragment area ratio (FAR), sagittal angle (θ), and fragment height (FH) were measured to assess the morphological characteristics of the PMF.

Results

The PMF in the SER group mainly had a posterolateral shape, whereas that in the PER group mainly had a posteromedial two-part shape or a large posterolateral triangular shape (P = 0.02). The average cross angle was not significantly different between the two groups (SER group = 19.4°, PER group = 17.6°). The mean FLR and FH were significantly larger in the PER group than in the SER group (P = 0.024, P = 0.006). The mean fragment sagittal angle in the PER group was significantly smaller than that in the SER group (P = 0.017).

Conclusions

With regard to the articular involvement, volume, and vertical nature, the SER-type fracture tends to have a smaller fragment due to the rotational force, whereas the PER-type fracture tends to have a larger fragment due to the combination of rotational and axial forces.

Impact of Computed Tomography on Operative Planning for Ankle Fractures Involving the Posterior Malleolus

BACKGROUND

The purpose of this study was to (1) Determine the effect of computed tomography (CT) on identification of fractures involving the posterior malleolus, (2) determine its effect on operative indications, and (3) determine its effect on the overall operative plan.

METHODS

Patients with ankle fractures involving the posterior malleolus were identified. Only injuries with complete preoperative plain radiographs and a CT scan were included. Spiral tibia fractures and pilon variants were excluded. The plain radiographs were deidentified, randomized, and presented to 3 orthopedic surgeons. They were asked 3 questions: (1) Is this fracture simple or complex? (2) Does the injury require direct visualization and reduction? and (3) How would you position the patient and approach the fracture? The same process was repeated for the CT scans. A total of 376 posterior malleolus injuries were identified and 25 met the inclusion criteria.

RESULTS

A complex fracture pattern was identified on 44% of plain radiographs and 56% of CT scans. The surgeons chose to operate in 84% of cases based on plain radiographs and 92% of cases based on CT scan. The observers changed their operative approach or positioning 44% of the time after reviewing CT images. The interobserver and intraobserver correlation coefficients were moderate.

CONCLUSION

The use of CT scan changed operative positioning and approach in 44% of cases. There was no significant change in characterization or operative indications when comparing plain radiographs to CT scan. CT scan may be a valuable tool in the management of ankle fractures involving the posterior malleolus.

LEVEL OF EVIDENCE

Diagnostic Level III, comparative series.

Pathoanatomy and Associated Injuries of Posterior Malleolus Fracture of the Ankle

BACKGROUND

We present a classification system that progresses in severity, indicates the pathomechanics that cause the fracture and therefore guides the surgeon to what fixation will be necessary by which approach.

METHODS

The primary posterior malleolar fracture fragments were characterized into 3 groups. A type 1 fracture was described as a small extra-articular posterior malleolar primary fragment. Type 2 fractures consisted of a primary fragment of the posterolateral triangle of the tibia (Volkmann area). A type 3 primary fragment was characterized by a coronal plane fracture line involving the whole posterior plafond.

RESULTS

In type 1 fractures, the syndesmosis was disrupted in 100% of cases, although a proportion only involved the posterior syndesmosis. In type 2 posterior malleolar fractures, there was a variable medial injury with mixed avulsion/impaction etiology. In type 3 posterior malleolar fractures, most fibular fractures were either a high fracture or a long oblique fracture in the same fracture alignment as the posterior shear tibia fragment. Most medial injuries were Y-type or posterior oblique fractures. This fracture pattern had a low incidence of syndesmotic injury.

CONCLUSION

The value of this approach was that by following the pathomechanism through the ankle, it demonstrated which other structures were likely to be damaged by the path of the kinetic energy. With an understanding of the pattern of associated injuries for each category, a surgeon may be able to avoid some pitfalls in treatment of these injuries.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Open reduction in pilon variant posterior malleolar fractures: Radiological and clinical evaluation

BACKGROUND

Pilon variant posterior malleolar (PVPM) fractures significantly disrupt joint congruency and cause tibiotalar instability. They are often underestimated and inadequately treated.

PURPOSE

This study assessed the outcomes of surgical treatment of this subtype of malleolar fracture, and examined the importance of computed tomography (CT) in diagnosis and surgical treatment.

MATERIAL AND METHODS

CT images and radiographs of 67 patients with trimalleolar ankle fractures were retrospectively analyzed. Fourteen patients (6 women and 8 men) were studied. The mean age was 37.7 (range, 21-58) years, and mean follow-up period was 17.1 (range, 12-24) months. All patients underwent open reduction. Reconstruction of the joint surface was assessed with postoperative CT images. The outcomes were assessed with the American Academy of Orthopaedic Surgeons (AAOS) and Osteoarthritis (OA) scoring systems.

RESULTS

The ratio of PVPM fractures to trimalleolar ankle fractures was 20.1%. Postoperative CT images demonstrated that anatomic reconstruction was achieved in 11 patients. The mean AAOS scores were 85.6 in Type 1 and 81.1 in Type 2 cases. The mean OA scores were 1 in Type 1 and 1.1 in Type 2 cases (P>0.05). The only statistically significant difference between the 2 groups was in osteochondral impaction (P<0.05).

CONCLUSION

CT imaging is essential for the accurate diagnosis and management of PVPM fractures. Posteromedial and posterolateral incisions enable direct exposure, and therefore facilitate joint surface reconstruction.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Operative Treatment of Posterior Malleolar Fractures

Fractures of the posterior malleolus can occur in conjunction with fibular and medial malleolar fractures or in isolation. The indications for fixation of the posterior malleolus remain controversial except for the fragment sizes. A number of different surgical approaches and techniques for internal fixation of posterior malleolar fractures have been reported. Newer techniques such as direct exposure and plating of the posterior malleolus are chosen more frequently than traditional techniques of indirect reduction and percutaneous screw fixation. These attributes help to minimize the occurrence of postoperative complications.

The correlation of the morphological changes of ankle point and ankle joint function after surgery on the Ruedi-Allgouer type III Pilon fracture: A case series study

BACKGROUND

To analyze the relationship between imaging findings and postoperative curative effect by measuring the morphology of the ankle mortise in patients with the Ruedi-Allgouer type III Pilon fractures.

MATERIAL AND METHODS

Forty-seven patients with Ruedi-Allgouer type III Pilon fractures who underwent surgical treatment from January 2011 to January 2015 were retrospectively analyzed. At the last follow-up, x-rays of the affected ankle and the healthy side were measured. According to the Kitaoka score of ankle joint function at the last follow-up.

RESULTS

All patients were followed up for 18-24 months (mean 21 months). This study demonstrated that compared with the healthy side, the index of the width, depth, and coronal/sagittal angles of the ankle mortise were significantly different (P < 0.05) in the 47 patients except for the index of height (P > 0.05). According to the Kitaoka score, the difference between the affected and the healthy sides of each index of the ankle mortise was compared between the 3 groups. That is, the intraoperative treatment of the width and depth of the ankle mortise as well as the coronal and sagittal angles of the ankle mortise were significantly correlated with the postoperative curative effect.

CONCLUSION

The intraoperative treatment of ankle mortise width, depth, and ankle coronal/sagittal angle in patients with severe Pilon fractures has a significant impact on postoperative efficacy. In order to prevent the occurrence of traumatic arthritis, the anatomical morphology of the ankle should be restored as much as possible in the course of surgery.

The Role of Computed Tomography in Surgical Planning for Trimalleolar Fracture. A Survey of OTA Members

OBJECTIVE

Does the additional information provided by computed tomography (CT) alter surgeons' treatment plans for trimalleolar ankle fracture?

DESIGN

Prospective.

SETTING

Electronic survey.

PATIENTS/PARTICIPANTS

Members of the OTA.

INTERVENTION

Compare management of trimalleolar ankle fracture before and after CT.

MAIN OUTCOME MEASUREMENTS

Compare types of fixation used, indication for fixation, and approach need for fixation before and after CT.

RESULTS

Overall, OTA members' operative technique changed in 430 of the 1710 (25.1%) cases after review of the CT images. Of the 430 observations in which the operative technique was altered, the surgeon had initially stated that they would not have requested a CT in 51.2% incidences. When analyzing if CT affected whether or not operative fixation was indicated, a total of 16.3% responses changed. Surgeons were significantly more likely to change from no fixation to fixation (11.5%) than vice versa (4.8%) after reviewing CT imaging. A total of 17.8% of responses changed operative approach after reviewing the CT; 11.7% changed to open reduction internal fixation, whereas 6.1% changed away from open reduction internal fixation.

CONCLUSION

A consensus on the ideal treatment of trimalleolar fractures remains elusive, evidenced by a high variation in treatment preference, both before and after CT review. Our results demonstrate with the additional information delineated on CT, a surgeons' operative plan, technique, and approach often change. With greater than 25% of respondents changing their treatment strategy after seeing CT imaging, radiographs alone limited surgeon understanding of fracture pattern. Because of difficulty understanding the posterior fracture fragment, we recommend preoperative CT on all trimalleolar fractures.

LEVEL OF EVIDENCE

Diagnostic Level V. See Instructions for Authors for a complete description of levels of evidence.

Treatment of Medial Malleolus or Pure Deltoid Ligament Injury in Patients with Supination-External Rotation Type IV Ankle Fractures

OBJECTIVE

To investigate the effect of internal fixation on postoperative ankle function in patients with supination-external rotation type IV ankle fractures, including medial malleolus fractures and deltoid ligament injury.

METHODS

Between January 2012 and June 2014, patients with medial structure injuries were enrolled in this study and assigned to the medial malleolus fracture group or the deltoid ligament group. The surgical procedures for the two groups were documented. The follow-up endpoint was the time point when the steel plate or screw was removed from the lateral ankle. The Olerud-Molander ankle scoring system was used to assess ankle function.

RESULTS

A total of 84 patients with supination-external rotation type IV ankle fractures had complete medical records and were included in this study. The average age of the patients was 44.16 years (range, 15-75). The patient sample included 39 males and 45 females. Overall, 49 patients (19 males and 30 females) suffered a medial malleolus fracture. The average age of these patients was 40.20 years (range, 15-75). Patients with a posterior malleolar fracture fragment >25% of the articular surface accounted for 81.6% (40 patients) of these patients. Overall, 35 patients (20 males and 15 females) experienced a deltoid ligament injury. The average age of these patients was 44.21 years (range, 17-73). Patients with a posterior malleolar fracture fragment >25% of the articular surface accounted for 11.5% (four patients) of these patients. Open reduction was performed in patients with medial malleolus fractures, and two 4.0-mm cannulated screws were used to fixate the posterior malleolus and the medial malleolus. The suture-anchor technique was used to repair the ligaments in patients with deltoid ligament injuries. The follow-up endpoint was the time point when the steel plate and screws were removed from the lateral ankle in patients. The average follow-up period was 13.4 months (range, 11-17). The Olerud-Molander ankle scoring system was used to assess postoperative ankle function. The average score for the patients in the medial malleolus fracture group was 90.3 points (range, 85-95). The average score for the patients in the deltoid ligament injury group was 87.7 points (range, 80-95). No significant differences were found in the scores between the two groups.

CONCLUSION

Medial malleolus fracture and deltoid ligament injury are two different presentations of supination-external rotation type IV ankle fractures. Anatomic reduction of the articular surface concurrent with restoration of ankle stability can achieve favorable results for these two injuries.

Posterior Malleolar Fractures: Changing Concepts and Recent Developments

Injuries to the posterior malleolus are of prognostic relevance in ankle fracture-dislocations. The three-dimensional outline of the fragments as reflected by computed tomography classification, involvement of the fibular notch, and the presence of intercalary fragments seem to be of greater therapeutic relevance than the size of the fragment and amount of the articular surface involved. Operative treatment aims at reconstruction of the posterior tibial plafond, the fibular notch, and the integrity of the posterior inferior tibiofibular syndesmosis. Direct open reduction and fixation of posterior malleolus fragments via posterior approaches is biomechanically more stable than indirect reduction and anteroposterior screw fixation.

Modified posteromedial approach for treatment of posterior pilon variant fracture

Background

Posterior pilon variant fracture is a recently described posterior malleolus fracture characterized by the involvement of both posterolateral and posteromedial malleolar fragment. The associated surgical approach remains controversial. The aim of this study was to present the application of modified posteromedial approach in the treatment for posterior pilon variant fracture.

Methods

Sixteen patients were identified with posterior pilon variant fractures. All fractures were operated via modified posteromedial approach. Fragment length ratio, area ratio and height were measured as morphologic assessments. The clinical outcome was evaluated with American Orthopaedic Foot & Ankle Society ankle-hind foot score and visual analogue scale. Radiological images were evaluated using osteoarthritis-score.

Results

According to the radiological measurements, the average fragment length ratio of posteromedial and posterolateral fragment was 25.3 and 31.5 % respectively. All fractures healed within a mean period of 13.1 weeks without malalignment or articular step-off. Fourteen patients were followed up, and all achieved good or excellent ankle function. The average score of American Orthopaedic Foot & Ankle Society and visual analogue scale at rest, motion and weight bearing walking was 85.6 and 0.25, 0.81, 1.31 respectively.

Conclusion

Modified posteromedial approach provides an alternative surgical treatment for posterior pilon variant fractures, and the short-term outcome was good.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1182-9) contains supplementary material, which is available to authorized users.

State-of-the-Art in Ankle Fracture Management in Chile

The ankle represents the most commonly injured weightbearing joint in the human body. They are typically the result of low-energy, rotational injury mechanisms. However, ankle fractures represent a spectrum of injury patterns from simple to very complex, with varying incidence of posttraumatic arthritis. Stable injury patterns can be treated nonoperatively; unstable injury patterns are typically treated operatively given that they could lead to severe arthritis if not properly addressed.