Trimalleolar fracture with involvement of the entire posterior plafond

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.

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.

OUTCOMES AFTER UNSTABLE FRACTURES OF THE ANKLE: WHAT'S NEW? A SYSTEMATIC REVIEW

BACKGROUND

Unstable ankle fractures are very frequent. Given the instability, they often require surgical treatment, but literature scarcely reports on the outcomes of their management.

QUESTIONS/PURPOSES

For this systematic review we asked: (1) What are the outcomes in treatment of unstable ankle fractures? (2) What about complications of treatment in unstable fractures? (3) What factors influence the outcomes? (4) What about the role of the posterior malleolus?

METHODS

The electronic databases PubMed, Scopus, and Embase were interrogated using the search terms "bimalleolar" or "trimalleolar" and "fracture". Studies were included if they reported on: (1) bimalleolar or trimalleolar fracture in adults; (2) treatment; (3) outcomes reported by scales; (4) follow-up. The final review included 33 studies. The quality of the studies was evaluated with the Methodological Index for Non-randomized Studies (MINORS) questionnaire.

RESULTS

All the outcomes of the thirty-three selected studies were analyzed.

DISCUSSION

Surgical fixation of unstable ankle fractures should always be performed within the first 48 hours from the trauma, preventing instability and post-traumatic osteoarthritis. Surgeon should consider factor may influence functional outcomes. Posterior malleolar fractures should be fixed regardless the size, considering some individual factors.

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.

Evaluation of Ankle Fractures in 228 Patients From a Single Center Using Three-Dimensional Computed Tomography Mapping

Purpose: The ankle joint has a complex anatomy structure with many causative factors and various injury mechanisms, and the clinical presentation of ankle fractures is diverse. This study aimed to analyze the characteristics of ankle fractures by applicating three-dimensional fracture line mapping technique. Methods: A retrospective study was conducted on 228 patients with ankle fractures. Three-dimensional reconstruction was performed by CT images and the fracture reconstruction model was superimposed onto a standard model of the tibiofibula for fracture line drawing. Then the fracture lines were converted into a three-dimensional coordinate point data set. And the fracture line maps as well as the fracture line heat maps were generated in 3-Matic software and Unigraphics NX software, respectively. Results: The dense area of the fibular fracture lines was located above the tibiofibular joint ligament and wrapped obliquely around the distal fibula from the anterior edge of the fibular neck. The fibular fracture line could be divided into three categories according to the degree of denseness. The dense area of the tibial fracture line is located within the anterior tibial fornix, the anterolateral corner, and the fibular notch. The tibial fracture lines can be classified into four categories according to the density of the fracture lines. The combined medial malleolus + posterior malleolar fracture line situation was found to be not encompassed by the existing AO and Lauge-Hansen (LH) classification systems according to this classification. Conclusion: The 3D fracture line mapping technique can better reflect the distribution of ankle fracture lines and could help to establish a new ankle fracture typing system in the future.

Distribution of posterior malleolus fracture lines in ankle fracture of supination-external rotation

INTRODUCTION

Supination-external rotation ankle fracture is one of the most common fractures. Studies on the fracture line distribution of this fracture type are limited. The purpose of this study is to explore the distribution characteristics of intra-articular posterior malleolus fracture lines in supination-external rotation.

HYPOTHESIS

Most of the fracture lines are concentrated in a particular area.

MATERIAL AND METHODS

Computed tomography scans of a consecutive series of 70 ankle fractures of supination-external rotation were used for this study. The DICOM files were loaded into Mimics 16.0 for 3D reconstruction of the distal tibial articular surface. The intra-articular posterior malleolus fracture lines were identified after virtual fracture reduction. All the fracture lines were drawn on one picture of the distal tibial articular surface after standardization before a heat map was created based on the frequency of fracture lines.

RESULTS

Although the distribution of posterior malleolus intra-articular fracture lines varied, most of them were concentrated in an arcuate zone. The ratios of the area of posterior fracture fragment to the total area of articular surface averaged 14.96% (range, from 2.23% to 38.45%). They were most likely to enter the articular surface at 20.4% of the tangent of the posterior edge in a standardized image and exit at 58.7% of the tangent of the lateral edge.

CONCLUSIONS

In ankle fractures of supination-external rotation, most intra-articular posterior malleolus fracture lines may be distributed regularly in an arcuate zone of the articular surface.

LEVEL OF PROOF

V; Descriptive research.

Current management of trimalleolar ankle fractures

A trimalleolar ankle fracture is considered unstable and treatment is generally performed operatively. Computed tomography is important for the operative planning by providing an elaborated view of the posterior malleolus.

Trimalleolar ankle fractures have a rising incidence in the last decade with up to 40 per 100,000 people per year. With a growing number of elderly patients, trimalleolar ankle injuries will become more relevant in the form of fragility fractures, posing a particular challenge for trauma surgeons.

In patients with osteoporotic trimalleolar ankle fractures and relevant concomitant conditions, further evidence is awaited to specify indications for open reduction and internal fixation or primary transfixation of the ankle joint.

In younger, more demanding patients, arthroscopic-assisted surgery might improve the outcome, but future research is required to identify patients who will benefit from assisted surgical care.

This review considers current scientific findings regarding all three malleoli to understand the complexity of trimalleolar ankle injuries and provide the reader with an overview of treatment strategies and research, as well as future perspectives.

Cite this article: EFORT Open Rev 2021;6:692-703. DOI: 10.1302/2058-5241.6.200138

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.

Acute syndesmotic injuries in ankle fractures: From diagnosis to treatment and current concepts

A stable and precise articulation of the distal tibiofibular syndesmosis maintains the tibiofibular relationship, and it is essential for normal motion of the ankle joint. The disruption of this joint is frequently accompanied by rotational ankle fracture, such as pronation-external rotation, and rarely occurs without ankle fracture. The diagnosis is not simple, and ideal management of the various presentations of syndesmotic injury remains controversial to this day. Anatomical restoration and stabilization of the disrupted tibiofibular syndesmosis is essential to improve functional outcomes. In such an injury, including inadequately treated, misdiagnosed and correctly diagnosed cases, a chronic pattern characterized by persistent ankle pain, function disability and early osteoarthritis can result. This paper reviews anatomical and biomechanical characteristics of this syndesmosis, the mechanism of its acute injury associated to fractures, radiological and arthroscopic diagnosis and surgical treatment.

Posterior-Based Approaches to Open Reduction Internal Fixation of Bimalleolar and Trimalleolar Fractures: A Systematic Review and Meta-analysis

Although there is growing evidence supporting posterior-based surgical approaches to open reduction internal fixation (ORIF) of malleolar fractures, the lateral approach still remains the standard of care for this injury. The purpose of this review was to integrate the results of several studies investigating outcomes following posterior-based approaches to the ORIF of malleolar fractures. The literature search was undertaken using PubMed, the Cochrane Library, and Embase. Crude event rates for fracture healing and postoperative complications were calculated. When possible, meta-analyses were conducted to estimate the relative risk of these outcomes between patients treated by posterior-based approaches versus other approaches to ORIF of malleolar fractures. Twenty-two studies were eligible, and 4 studies were included in the meta-analyses. The healing rate was 100% in all patients, regardless of the surgical approach. Overall, 1.26% of patients developed an infection, 0.63% required reoperation, 1.13% experienced aseptic loosening, 5.53% experienced pain after treatment, and 2.52% experienced symptomatic hardware. No malunion or heterotopic ossification was reported in any study. Among patients treated with a posterior-based approach, the most frequently reported complication was infection (2.50%), with lower rates of reoperation and postoperative pain. Patients with trimalleolar fractures experienced slightly poorer outcomes. Patients treated by posterior-based approaches had a significantly increased risk of infection (p = .010) relative to those treated by the lateral approach; patients treated by the lateral approach had a significantly increased risk of pain after surgery (p = .004) and symptomatic hardware (p = .007). This study brought together evidence that posterior-based surgical approaches and non-posterior-based approaches to ORIF are effective in healing malleolar fractures, with significant differences in specific postoperative complications that need to be further explored.

Quantitative evaluation of posterior talar subluxation in posterior malleolar fractures: A preliminary study

BACKGROUNDS

Although ankle posterior subluxation is one of the major mechanisms by which posterior malleolar fractures (PMF) contribute to a worse prognosis, there is no parameter to address it quantitatively. So, we suggest a method that can evaluate posterior talar subluxation quantitatively in PMF.

METHODS

We retrospectively analyzed 37 patients with posterior malleolar fractures. The patients were divided into two groups: PMF without posterior talar subluxation (n = 18) and with posterior talar subluxation (n = 19). We measured the distance between the arc center of the talus and the anterior tibia (TAD), the percentage of articular involvement of the fracture fragment, the inter-fragment distance (IFD) and articular step-off. We analyzed significant differences and the correlations between the two groups for each index. The estimated area of the receiver operating characteristic (ROC) curve was calculated, and cutoff values were suggested to discriminate posterior talar subluxation.

RESULTS

TAD, IFD, and articular step-off were significantly greater in patients with posterior talar subluxation. (TAD: 14.3 vs. 2.8 mm, p < 0.001, IFD: 7.8 vs. 4.0 mm, p < 0.001, articular step-off: 3.6 vs. 2.0 mm, p = 0.004). The ROC curve showed that TAD was most useful to determine cutoff values for posterior talar subluxation. The area under the curve for TAD was 1.000, and the appropriate cutoff value was 5 mm. When a TAD of > 5 mm was used as a threshold, a sensitivity of 100% and a specificity of 100% were achieved in determining the presence of posterior talar subluxation. Also, higher TAD was correlated with IFD and articular step-off.

CONCLUSIONS

TAD can be a useful parameter for evaluating the posterior talar subluxation in PMF. It can reflect not only the degree of fracture displacement but also posterior talar subluxation quantitatively.

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.

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.

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.

Loss of Rab25 promotes the development of skin squamous cell carcinoma through the dysregulation of integrin trafficking

Rab25 can function as both a tumor suppressor and a tumor promoter across different tissues. This study sought to clarify the role of Rab25 as a tumor suppressor in skin squamous cell carcinoma (SCC). Rab25 loss was closely associated with neoplastic transition in both humans and mice. Rab25 loss was well correlated with increased cell proliferation and poor differentiation in human SCC. While Rab25 knockout (KO) in mice did not induce spontaneous tumor formation, it did significantly accelerate tumor generation and promote malignant transformation in a mouse two-stage skin carcinogenesis model. Xenografting of a Rab25-deficient human keratinocyte cell line, HaCaT, also elicited neoplastic transformation. Notably, Rab25 deficiency led to dysregulation of integrins β1, β4, and α6, which matched well with increased epidermal proliferation and impaired desmosome-tight junction formation. Rab25 deficiency induced impairment of integrin recycling, leading to the improper expression of integrins. In line with this, significant attenuation of integrin β1, β4, and α6 expression was identified in human SCCs where Rab25 was deficient. Collectively, these results suggest that loss of Rab25 promotes the development and neoplastic transition of SCC through dysregulation of integrin trafficking. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Posterior malleolar fracture morphology determines outcome in rotational type ankle fractures

INTRODUCTION

Rotational type ankle fractures with a concomitant fracture of the posterior malleolus are associated with a poorer clinical outcome as compared to ankle fractures without. However, clinical implications of posterior malleolar (PM) fracture morphology and pattern have yet to be established. Many studies on this subject report on fragment size, rather than fracture morphology based on computed tomography (CT). The overall purpose of the current study was to elucidate the correlation of PM fracture morphology and functional outcome, assessed with CT imaging and not with -unreliable- plain radiographs.

METHODS

Between January 2010 and May 2014, 194 patients with an operatively (ORIF) treated ankle fracture, were prospectively included in the randomized clinical EF3X-trial at our Level-I trauma center. The current study retrospectively included 73 patients with rotational type ankle fractures and concomitant fractures of the posterior malleolus. According to the CT-based Haraguchi fracture morphology, all patients were divided into three groups: 20 Type I (large posterolateral-oblique), 21 Type II (transverse medial-extension) and 32 Type III (small-shell fragment). At 12 weeks, 1 year and 2 years postoperatively the Foot and Ankle Outcome Scores (FAOS) and SF-36 scores were obtained, with the FAOS domain scores at two years postoperative as primary study outcome. Statistical analysis included a multivariate regression and secondary a mixed model analysis.

RESULTS

Haraguchi Type II PM ankle fractures demonstrated significantly poorer outcome scores at two years follow-up compared to Haraguchi Types I and III. Mean FAOS domain scores at two years follow-up showed to be significantly worse in Haraguchi Type II as compared to Type III, respectively: Symptoms 48.2 versus 61.7 (p = 0.03), Pain 58.5 versus 84.4 (p < 0.01), Activities of Daily Living (ADL) 64.1 versus 90.5 (p < 0.01).

CONCLUSION

Posterior malleolar ankle fractures with medial extension of the fracture line (i.e. Haraguchi Type II) are associated with significantly poorer functional outcomes. The current dogma to fix PM fractures that involve at least 25-33% of the tibial plafond may be challenged, as posterior malleolar fracture pattern and morphology - rather than fragment size - seem to determine outcome.

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.

Characteristics and proposed classification system of posterior pilon fractures

Posterior pilon fractures involve the medial malleolus (MM). Our purpose was to define the characteristics of posterior pilon fractures, and propose a classification system based on fracture morphology and type of management.The records of patients with posterior pilon fractures treated from 2011 to 2015 were retrospectively reviewed. The injury mechanism, fracture morphology, surgical approach, and follow-up results were reviewed and analyzed. This study was approved by the Institutional Review Board of PLA Army General Hospital.Thirty-six patients, 18 males and 18 females (mean age: 48.9 years) were included in the study. Four characteristics were used to define posterior pilon fractures. A simple posterolateral approach or a combined posterolateral and posteromedial approach was used for reduction and fixation in all patients. The mean follow-up time was 28.2 months, and at the end of follow-up, the mean American Orthopedic Foot and Ankle Society Score (AOFAS) was 82.5 points (range: 35-100 points). Based on injury mechanism and fracture morphology, we classified posterior pilon fractures into 3 types that suggest the optimal surgical approach: type I, a single complete fracture fragment; type II, a posterior malleolus fracture with 2 subtypes; type III, a posterior malleolus fracture associated with complete MM fracture with 2 subtypes.The proposed classification system based on injury mechanism and fracture morphology can guide the surgical approach to maximize outcomes.

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.

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.

Longterm outcome of 886 posterior malleolar fractures: A systematic review of the literature

INTRODUCTION

The objective of the present study was to review the current data on the long-term outcomes of posterior malleolar fractures, with special emphasis on the role of the type of treatment, surgical approach, and reduction and internal fixation.

METHODS

The search was limited to skeletally mature patients. Major databases were searched from 1978 to 2014 to identify studies relating to functional outcome, subjective outcome, and radiographic evaluation at least 2 years after either surgical or conservative treatment of posterior malleolar fractures.

RESULTS

Of 68 initially relevant studies, 19 met our inclusion criteria. A total of 886 fractures were identified in 885 patients. The mean sample size-weighted follow-up period was 3.7 years. Comparable results are achieved when comparing open reduction and internal fixation to conservative treatment for posterior malleolar fractures.

DISCUSSION

Current consensus suggests posterior malleolar fragments comprising of >25% of the distal tibial plafond as seen on a true lateral radiograph and fragments with more than 2mm dislocation require open reduction and internal fixation of the fragment. The current consensus on treatment of posterior malleolar fractures is neither supported nor disapproved by the available evidence.

Posterior Malleolar Fracture Patterns

OBJECTIVE

To characterize posterior malleolar fracture morphology using Cole fracture mapping and to study reliability of quantification of 3-dimensional computed tomography (CT)-modeling for posterior malleolar fractures with respect to quantification of fragment size (in cubic millimeter) and true articular involvement (in square millimeter).

METHODS

CT scans of a consecutive series of 45 patients with an ankle fracture involving the posterior malleolus were reconstructed to calculate (1) fracture maps, (2) fragment volume, (3) articular surface of the posterior malleolar fragment, (4) articular surface of intact tibia, and (5) articular surface of the medial malleolus by 3 independent observers. Three-dimensional animation of this technique is shown on www.traumaplatform.org.

RESULTS

Fracture mapping revealed (1) a continuous spectrum of posterolateral oriented fracture lines and (2) fragments with posterolateral to posteromedial oriented fracture lines extending into the medial malleolus. Reliability of measurements of the volume and articular surface of posterior malleolar fracture fragments was defined as almost perfect according to the categorical system of Landis (interclass coefficient, range, 0.978-1.000).

CONCLUSIONS

Mapping of posterior malleolar fractures revealed a continuous spectrum of Haraguchi III to I fractures and identified Haraguchi type II as a separate pattern. Quantification of 3-dimensional CT-modeling is reliable to assess fracture characteristics of posterior malleolar fracture fragments. Morphology might be more important than posterior malleolar fracture size alone for clinical decision making.

Ankle fracture spur sign is pathognomonic for a variant ankle fracture

BACKGROUND

The hyperplantarflexion variant ankle fracture is composed of a posterior tibial lip fracture with posterolateral and posteromedial fracture fragments separated by a vertical fracture line. This infrequently reported injury pattern often includes an associated "spur sign" or double cortical density at the inferomedial tibial metaphysis. The objective of this study was to quantitatively establish the association of the ankle fracture spur sign with the hyperplantarflexion variant ankle fracture.

METHODS

Our clinical database of operative ankle fractures was retrospectively reviewed for the incidence of hyperplantarflexion variant and nonvariant ankle fractures as determined by assessment of injury radiographs, preoperative advanced imaging, and intraoperative observation. Injury radiographs were then evaluated for the presence of the spur sign, and association between the spur sign and variant fractures was analyzed.

RESULTS

The incidence of the hyperplantarflexion variant fracture among all ankle fractures was 6.7% (43/640). The spur sign was present in 79% (34/43) of variant fractures and absent in all nonvariant fractures, conferring a specificity of 100% in identifying variant fractures. Positive predictive value and negative predictive value were 100% and 99%, respectively.

CONCLUSION

The ankle fracture spur sign was pathognomonic for the hyperplantarflexion variant ankle fracture. It is important to identify variant fractures preoperatively as patient positioning, operative approach, and fixation construct of variant fractures often differ from those employed for osteosynthesis of nonvariant fractures. Identification of the spur sign should prompt acquisition of advanced imaging to formulate an appropriate operative plan to address the variant fracture pattern.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

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

BACKGROUND

Substantial attention has recently been placed on fractures of the posterior malleolus. Fracture extension to the posteromedial rim ("posterior pilon variant") may result in articular incongruity and talar subluxation. Current classification systems fail to account for these fractures. The relative frequency of this fracture, its associated patient characteristics, and the reliability of its diagnosis have never been reported in such a large series.

METHODS

We retrospectively identified 270 patients who met our inclusion criteria. Basic demographic data were collected. The fractures were classified according to Lauge-Hansen and AO/OTA. Additional radiographic data included whether the fracture involved the posterior malleolus and whether the fracture represented a posterior pilon variant. Univariate statistical methods, chi-square analysis, and interobserver reliability were assessed.

RESULTS

The relative frequency of posterior malleolus fracture was 50%. The relative frequency of the posterior pilon variant was 20%. No significant difference was noted with respect to the frequency of posterior malleolar or posterior pilon variant between the subgroups of the AO/OTA and Lauge-Hansen classification systems when compared to the overall fracture distribution. Patients with posterior malleolar fractures and posterior pilon variants were significantly older. Females were significantly more likely than men to sustain posterior malleolar fractures and posterior pilon variants. Patients with diabetes trended toward a greater risk of both types of fractures. Interobserver reliability data revealed substantial agreement for posterior malleolar fractures and posterior pilon variants.

CONCLUSION

These data represent the highest reported rate of posterior malleolar involvement in operatively treated ankle fractures and is the first to describe the percentage of the posterior pilon variant in such a large series. The interobserver reliability data demonstrate substantial agreement in identification of posterior malleolar fractures and the posterior pilon variant based on plain radiographs. Certain patient characteristics such as age, sex, and diabetes may be associated with these fractures.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Open reduction and internal fixation of posterior pilon fractures with buttress plate

Objective:

Posterior pilon fractures are rare injuries and have not yet gained well recognition. The purpose of this study was to present the treatment outcome for patients with posterior pilon fractures treated with buttress plate.

Method:

In this retrospective study we identified patients with posterior pilon fractures of the distal tibia who had undergone open reduction and internal fixation at our institute. Between January 2007 and December 2009, 10 patients (mean age, 46.5 years) who had undergone buttress plating via either a posterolateral approach or a dual posterolateral-posteromedial approach, were selected. All 10 patients were available for follow-up. The clinical outcome was evaluated with the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the visual analogue scale (VAS). The radiological evaluation was performed using the osteoarthritis-score (OA-score).

Results:

Satisfactory reduction and stable fixation were accomplished in all patients. At a mean follow-up of 36.2 months, all patients had good radiological results and showed satisfactory clinical recovery. The mean AOFAS sore was 87.8, the mean OA-score was 0.6, and the mean VAS scores during rest, active motion, and weight-bearing walking were 0.6, 0.8, and 1.4, respectively.

Conclusion:

Buttress plating for posterior pilon fractures gave satisfactory clinical outcomes. It also ensured rigid fixation which in turn enabled earlier postoperative mobilization. Level of Evidence IV, Retrospective Study.