Posterior Malleolar Ankle Fractures: An Effort at Improving Outcomes

Traditional postero-medial ankle approach for Bartonícek type III in Volkmann Fractures: Is it useful?

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Morphology of occult posterior malleolus fractures associated with tibial shaft fractures

Aims

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

Methods

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

Results

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

Conclusion

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

Treatment Strategy for Posterior Malleolar Fractures: Different Operative Strategies Are Needed for Each Morphological Type

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

2B or not 2B, should this not be the question? Comparison of 3D Surface Rendering CT to Plain Radiographs for Characterization of Posterior Malleolar Fracture Morphology

Background

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

Methods

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

Results

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

Conclusion

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

Level of Evidence

Level III, retrospective comparative study.

Clinical relevance of current patient-reported outcome measures for ankle fracture: surgeons' perspective

Objectives

Determine the relevance of the most frequently used patient-reported outcome measures (PROMs) for monitoring patient recovery after ankle fracture, from the clinical perspective of orthopaedic trauma surgeons, given lack of validated PROMs.

Design

Prospective cohort.

Setting

Orthopaedic Trauma Association committee meetings, electronic correspondence.

Patients/Participants

Orthopaedic trauma surgeons.

Intervention

Delphi method for consensus activities.

Level of Evidence

IV.

Main Outcome Measurements

Most clinically relevant PROMs for ankle fracture recovery.

Results

Several English-language PROMs were identified based on use in literature and relevance to ankle fractures. 7 were selected by expert consensus. These are the Ankle Fracture Outcome of Rehabilitation Measure (A-FORM), Foot and Ankle Ability Measure (FAAM), American Academy of Orthopaedic Surgeons (AAOS), Foot and Ankle Disability Index (FADI) Score, Lower Extremity Functional Scale (LEFS), Olerud-Molander Ankle Score (OMAS), and Patient-Reported Outcome Measurement Information System Physical Function (PROMIS PF). The most clinically relevant PROM is the A-FORM, followed by the AAOS, LEFS, PROMIS PF, FADI, and OMAS, and the least clinically relevant overall, the FAAM.

Conclusions

Understanding which PROM best matches physician expectations for tracking recovery is an important step toward a robust, evidence-based approach to patient care. The A-FORM was identified as the most clinically relevant among the most used PROMs. These results will aid surgeons, clinicians, and scientists to identify a uniformly, clinically relevant PROM for the treatment and study of outcomes and recovery after isolated ankle fracture.

The arterial risk posed by the posterolateral approach: An anatomical cadaveric study of the fibular artery and its variability

The posterior malleolus of the tibia is commonly accessed surgically through the posterolateral approach. This approach gives good access to the fibula and lateral aspect of the posterior tibia, however; there is little known on the vascular risks with this approach. The aim of this study was to assess and describe the anatomy of the fibular artery and its branches at the ankle region and relate it to the surgical access of the posterior malleolus. Eleven cadaveric foot and ankle specimens were dissected in layers, preserving the fibular artery, anterior tibial artery (ATA), and posterior tibial artery (PTA). Five distinct variations were found in the fibular artery: variable terminal branching with a hyperplastic fibular artery; a superficially located fibular artery; variation in the level and number of anastomoses; variation in the muscular branches; and a variable anterior perforating branch. The mean proximal distance from a horizontal line drawn through the medial protuberance of the medial malleolus of the tibia (horizontal line reference point-HLRP) to the posterior communicating branch of the fibular artery was 37.93 mm (range 19.03-85.43 mm). The mean proximal distance between HLRP and the anterior perforating branch of the fibular artery was 44.23 mm (range 35.44-62.32 mm). In 10 specimens, the fibular artery was immobile distal to its anterior perforating branch. The posterolateral approach specifically puts the fibular artery at risk and knowledge of its anatomy and variability is important when undertaking this approach. Understanding the common variations within the ankle's arterial anatomy can help surgeons protect these vessels from damage during the surgical approach.

Posterior Malleolus Fracture Fixation In Lateral Decubitus Position: Surgical Technique and Results in 60 Patients

The present study shows how posterior malleolus fractures (PMFs) and distal fibular fractures were fixed using the posterolateral approach with the patient in lateral decubitus position, not previously described in the literature. This technique has been used in 60 consecutive patients (42 women and 18 men; mean age 54.7; range 21-92 years), 33 of which presented as fracture dislocations from March, 2021 to December, 2023. After PMFs fixation in lateral decubitus position, release of the sacral support allowed patients to be placed supine (without de-sterilizing the operative field), in order to proceed with medial malleolus or posteromedial fragment fixation. Fractures were classified according to the Lauge Hansen classification as SER4 (n = 50), PER4 (n = 7), SAD (n = 1), and PAB (n = 2). Fractures were classified according to Rammelt & Bartonicek, as type B (n = 40), C (n = 13), and D (n = 7). During the same period of time 14 fractures involving the PM, classified as type A, were treated with indirect fixation, whilst 6 geriatric and/or poor mobility patients with fracture dislocations were treated with retrograde hindfoot nail fixation. Follow-up period ranged from 4-36 months (mean = 14.4; SD = 8.8). Complications occurred in 5 patients (8.3%; 3 had delayed (medial) wound healing, one developed CRPS and one required implants removal and arthroscopy because of metal irritation and stiffness). No deep infections, thromboembolic events, fracture malreductions or malunions were recorded and all patients returned to the preinjury mobilization status. In conclusion, PM fracture fixation was feasible and safely performed with patients in lateral decubitus position.

Fragment-Specific Fixation for Trimalleolar Fractures: Functional and Radiological Outcomes

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

Safety and exposure area in three different posteromedial surgical approaches for the treatment of ankle fractures. A cadaveric study

INTRODUCTION

This study aimed to compare the degree of posterior malleolar exposure, the tension of the flap containing the posteromedial neurovascular bundle (NVB), and the distance between the surgical incision and the NVB using three different posteromedial ankle approaches.

METHODS

Three approaches were compared: medial posteromedial (MePM) modified posteromedial (MoPM) and posteromedial (PM). We measured the minimal tension of the flap containing the NVB that allowed proper exposure. In the second stage, an axial cut was performed, and we measured the degree of posterior malleolar exposure and the distance between the incision and the NVB RESULTS: There were significant differences between the three approaches examined regarding the degree of posterior malleolar exposure and distance from the incision to the NBV,favoring the PM approach (71,00% ± 1.83 and 25.50 mm ± 4.20). The PM approach provided a significantly lower tension to the flap containing the posteromedial NVB (6.18 N ± 1.28) compared to the other two approaches CONCLUSION: The PM approach achieved the highest degree of posterior malleolar exposure, the lowest tension to the posteromedial NVB, and the greatest distance between the incision and the NBV. Thus, we believe it should be considered the approach of choicefor large fractures of the posteromedial aspect of the PM.

Reduction Quality in Posterior Malleolar Fractures Using a Modified Posteromedial Ankle Approach

Background

Anatomical reduction of posterior malleolar fracture is a key goal in achieving good functional outcomes in patients with ankle fractures. Although there are many approaches for managing this type of fracture, no studies have shown reduction quality of posterior malleolar fracture in postoperative CT scan using the modified posteromedial ankle approach.

Methods

A retrospective case series of 66 patients of 2 health centers with type 2, 3, and 4 posterior malleolar fractures according to Bartonicek classification treated using the modified posteromedial ankle approach was performed. The postoperative CT scan was used to assess syndesmotic reduction and articular step-off and residual gap in posterior malleolus reduction.

Results

Reduction of posterior malleolus fracture was determined to be <2 mm in 62 patients and >2 mm in 4 cases. Syndesmotic reduction quality was considered to be anatomical in 61 patients. Four patients showed mild anterior fibular translation in the axial plane and were not reoperated. One syndesmotic malreduction was considered poor.

Conclusion

In this study, we found that 92% (61 of 66) of patients with posterior malleolar fracture were reduced with <2 mm step-off using this modified posteromedial ankle approach and fracture fixation strategy.

Level of Evidence

Level IV, case series.

Utility of CT Scans for Detecting Operative Malleolar Fractures Associated With Tibial Shaft Fractures

OBJECTIVES

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

METHODS

DESIGN

Retrospective cohort study.

SETTING

Single level I trauma center.

PATIENT SELECTION CRITERIA

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

OUTCOME MEASURES AND COMPARISONS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

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

Frequent Sural Nerve Injury with Posterior Approach for Ankle Fracture Fixation

INTRODUCTION

The purpose of this study was to report the incidence of iatrogenic sural nerve injury in a large, consecutive sample of surgically managed ankle fractures and to identify factors associated with sural nerve injury and subsequent recovery. We hypothesize that a direct posterior approach may be associated with higher risk of iatrogenic sural nerve injury.

METHODS

A retrospective cohort study of 265 skeletally mature patients who sustained ankle fractures over a 2-year period was done. All were treated with open reduction and internal fixation of fractured malleoli. Patient, injury, and treatment features were documented. The presence (n = 26, 9.8%) of sural nerve injury and recovery of sural nerve function were noted.

RESULTS

All 26 sural nerve injuries were iatrogenic, occurring postoperatively after open reduction and internal fixation. Patients who sustained sural nerve injuries had more ankle fractures secondary to motor vehicle collisions (23.1% versus 9.2%), more associated trimalleolar fractures (69.2% versus 33.9%), and more Orthopaedic Trauma Association/AO 44B3 fractures (57.7% versus 25.1%), all P < 0.05. A posterior approach to the posterior malleolus through the prone position was used in 20.4% of patients. All 26 of the sural nerve injuries (100%) occurred when the patient was placed prone for a posterior approach, P < 0.001. Therefore, 26 of the 54 patients (48%) treated with a posterior approach sustained an iatrogenic sural nerve injury. 62% of patients had full recovery of sural nerve function with no residual numbness, and patients with nerve recovery had fewer associated fracture-dislocations (23.1% versus 100%, P = 0.003).

CONCLUSIONS

A posterior approach for posterior malleolus fixation was associated with a 48% iatrogenic sural nerve injury rate, with 62% recovering full function within 6 months of injury. Morbidity of this approach should be considered, and surgeons should be cautious with nerve handling.

LEVEL OF EVIDENCE

Level III, Therapeutic.

Ten year outcomes after non-fixation of the smaller posterior malleolar fragment: A retrospective cohort study

INTRODUCTION

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSION

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

LEVEL OF EVIDENCE

Level III - Retrospective cohort study.

Posterior tibialis tendon entrapment as a complication of posterior malleolar fractures in complex ankle fractures

Aims

Posterior malleolar (PM) fractures are commonly associated with ankle fractures, pilon fractures, and to a lesser extent tibial shaft fractures. The tibialis posterior (TP) tendon entrapment is a rare complication associated with PM fractures. If undiagnosed, TP entrapment is associated with complications, ranging from reduced range of ankle movement to instability and pes planus deformities, which require further surgeries including radical treatments such as arthrodesis.

Methods

The inclusion criteria applied in PubMed, Scopus, and Medline database searches were: all adult studies published between 2012 and 2022; and studies written in English. Outcome of TP entrapment in patients with ankle injuries was assessed by two reviewers independently.

Results

Four retrospective studies and eight case reports were accepted in this systematic review. Collectively there were 489 Pilon fractures, 77 of which presented with TP entrapment (15.75%). There were 28 trimalleolar fractures, 12 of which presented with TP entrapment (42.86%). All the case report studies reported inability to reduce the fractures at initial presentation. The diagnosis of TP entrapment was made in the early period in two (25%) cases, and delayed diagnosis in six (75%) cases reported. Using modified Clavien-Dindo complication classification, 60 (67%) of the injuries reported grade IIIa complications and 29 (33%) grade IIIb complications.

Conclusion

TP tendon was the commonest tendon injury associated with pilon fracture and, to a lesser extent, trimalleolar ankle fracture. Early identification using a clinical suspicion and CT imaging could lead to early management of TP entrapment in these injuries, which could lead to better patient outcomes and reduced morbidity.

Considerations with Fractures of the Posterior Malleolus in Ankle Fractures

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

Importance of computed tomography in posterior malleolar fractures: Added information to preoperative X-ray studies

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Biomechanical Efficacy of Three Methods for the Fixation of Posterior Malleolar Fractures: A Three-Dimensional Finite Element Study

Introduction: We investigated the biomechanical behaviour of different fixations of the tibial posterior malleolus (TPM), simulating distinct situations of involvement of the tibiotalar articular surface (TTAS) through a finite element model (FEM). Material and methods: A 3D computer-aided design model of the left ankle was obtained. The materials used were divided according to their characteristics into ductile and non-ductile, and all materials were assumed to be linear elastic, isotropic, and homogenous. Three different fracture lines of the TPM were defined, with sagittal angles of 10°, 25°, and 45°. For biomechanical comparison, different constructions using a trans-syndesmotic screw (TSS) only (Group T), a one-third tubular plate only with (Group PT) and without (Group PS) a TSS, and a locked compression plate with (Group LCPT) and without (Group LCPS) a TSS were tested. FEM was used to simulate the boundary conditions of vertical loading. Load application regions were selected in the direction of the 700 N Z-axis, 90% on the tibia and 10% on the fibula. Data on the displacement and stress in the FEM were collected, including the total principal maximum (MaxT) and total principal minimum (MinT) for non-ductile materials, total displacement (desT), localized displacement at the fragment (desL), localized displacement at syndesmosis (desS), and Von Mises equivalent stress for ductile materials. The data were analysed using ANOVA and multiple comparison LSD tests were used. Results: For TPM fractures with sagittal angles 10° and 25°, desL in the PT and LCP groups was significantly lower, as well as Von Mises stress in Group LCPT in 10°, and PT and LCPT groups in 25°. For TPM fractures with a sagittal angle of 45°, desL in the LCP group and Von Mises stress in Group LCPS and LCPT were significantly lower. We found that any TPM fracture may indicate instability of the distal tibiofibular syndesmosis, even when the fragment is small. Conclusion: Our study showed that in fragments involving 10% of the TTAS, the use of a TSS is sufficient, but when the involvement is greater than 25% of the TTAS, either a non-locked or locked plate must be used to buttress the TPM. In posterior fragments affecting 45% or more of the TTAS, the use of a locking plate is recommended.

Safety of the modified posteromedial approach in complex ankle fractures: Comparative analysis versus posterolateral access

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Clinical outcomes of ankle fractures in sub-Saharan Africa: a systematic review

PURPOSE

Ankle fractures may cause disability and socioeconomic challenges, even when managed in a high-resource setting. The outcomes of ankle fractures in sub-Saharan Africa are not widely reported. We present a systematic review of the patient-reported outcomes and complications of patients treated for ankle fractures in sub-Saharan Africa.

METHODS

Medline, Embase, Google Scholar and the Cochrane Central Register of Controlled Trials were searched, utilising MeSH headings and Boolean search strategies. Ten papers were included. Data included patient demographics, surgical and non-surgical management, patient-reported outcome measures and evidence of complications.

RESULTS

A total of 555 patients with ankle fractures were included, 471 of whom were followed up (range 6 weeks-73 months). A heterogenous mix of low-quality observational studies and two methodologically poor-quality randomised trials demonstrated mixed outcomes. A preference for surgical management was found within the published studies with 87% of closed fractures being treated operatively. A total of five different outcome scoring systems were used. Most studies included in this review were published by well-resourced organisations and as such are not representative of the actual clinical practice taking place.

CONCLUSION

The literature surrounding the clinical outcomes of ankle fractures in sub-Saharan Africa is sparse. There appears to be a preference for surgical fixation in the published literature and considering the limitations in surgical resources across sub-Saharan Africa this may not be representative of real-life care in the region.

Anatomy of the Sural Nerve in the Posterolateral Approach to the Ankle: A Cadaveric Study

Sural nerve injury may occur during the posterolateral approach to the ankle during fracture fixation. We aimed to map its location in a posterolateral approach in cadaveric specimens. A posterolateral approach was used in 28 cadaver legs with the incision made halfway between the medial border of the fibula and the lateral border of Achilles tendon, extending proximally from the tip of the lateral malleolus. The sural nerve was identified and the distance from the distal tip of the incision to where it crossed the incision proximally was measured. The mean distance was 3.4 ± 1.2 (range 0.5-7.0) cm. In 22 cases (78.5%), the distance from the lowest part of the incision to the inferior part of the nerve was between 2.7 and 4.5 cm. The nerve did not cross the incision in 2 cases. We have demonstrated that the sural nerve crossed the posterolateral incision between 2.7 and 4.5 cm proximal to the tip of the fibula in the majority of cases. However, there remains individual anatomical variation, and we would recommend that care should be taken to look for the nerve closer to the Achilles tendon proximally and nearer the fibula distally. We hope that this information can help surgeons plan their approach and minimize iatrogenic injury to the sural nerve.

Posterior malleolus fracture: a mid-term follow-up

BACKGROUND

The treatment of posterior malleolar fractures is changing rapidly, and the evidence base is still catching up. This study aimed to assess the mid-term prognosis of posterior malleolar fractures based on different morphological types and provides evidence for the treatment of posterior malleolar fractures.

METHODS

We retrospectively analyzed the data of inpatients with posterior malleolar fractures from 1 January 2012 to 31 December 2019 at one high-volume tertiary trauma center. Fracture morphology was classified into small-shell fragment, single-fragment (small-fragment and large-fragment) and multifragment (double-fragment and compressive-fragment) by computed tomography according to our previous study. All patients were followed up at an average of 5.06 (range, 2.21-8.70) years. The Olerud-Molander Ankle Score (OMAS), EuroQol-5 Dimensions (EQ-5D) and American Orthopedic Foot and Ankle Society (AOFAS) score were recorded.

RESULTS

Seventy-nine patients were included, and 7 patients were classified into the small-shell group, 52 patients into the single-fragment group and 20 patients into the multifragment group. Of all the patients, the average OMAS, EQ-5D and AOFAS scores were 85.9, 82.8 and 92.5, respectively. In the single-fragment group, patients who underwent surgical fixation in the posterior malleolus had significantly better scores (P = 0.037, 0.033 and 0.027). Among the patients with small fragments, the surgical fixation group also had higher OMAS (93.1 ± 7.5 vs. 83.5 ± 19.5, P = 0.042) and AOFAS scores (98.1 ± 3.1 vs. 91.0 ± 14.1, P = 0.028). The mean OMAS, EQ-5D and AOFAS scores were 85.5, 85.7 and 91.7, respectively, in patients with multiple fragments who underwent surgical fixation.

CONCLUSION

This study shows that in fractures with a single fragment, surgical fixation of the posterior malleolar fragment led to a better prognosis in the midterm. All single fragments should be fixed regardless of size. Fixation of the posterior region in all single- and multi-fragments in posterior malleolar fractures led to satisfactory outcomes.

LEVEL OF EVIDENCE

Level III, follow-up study.

Open fixation of the posterior malleolus increases the morbidity of trimalleolar ankle fracture fixation

PURPOSE

To assess the morbidity of open reduction internal fixation (ORIF) of posterior malleolus fractures (PMFs) in the setting of trimalleolar ankle fractures.

METHODS

A retrospective review of 79 trimalleolar ankle fractures was performed to identify need for syndesmotic fixation, blood loss, operative/tourniquet time, complications, and reoperations. Patients with PMF ORIF (n = 38) were compared to those with no fixation (n = 41). A subanalysis of patients with small PMFs (< 25%) was performed.

RESULTS

The PMF ORIF group required less syndesmosis fixation (proportional difference (PD) - 44.6%, 95% confidence interval (CI) - 61.8 to - 23.0%), had more blood loss (MD 20 ml, CI 0-40), longer operative times (MD 53.0 min, CI 35.9-70.1), longer tourniquet times (MD 26 min, CI 4-33), and had no difference in postoperative joint step-off or concentrically reduced joints. The PMF ORIF group had more postoperative complications (PD 26.9%, CI 6.3-44.8%) and a trend for more reoperations (PD 13.6%, CI -3.4 to 29.6%). Wound complications were more common in the PMF ORIF group (PD 26.5%, CI 6.9-43.6%), resulting in 5 (16.1%) irrigation and debridement procedures. On analysis of patients with small PMFs (n = 42), PMF ORIF (n = 15) resulted in longer operative/tourniquet times and had no observed difference in postoperative joint step-off, concentrically reduced joints, need for syndesmotic fixation, blood loss, or complications/reoperations.

CONCLUSION

PMF ORIF in the setting of trimalleolar ankle fractures was associated with increased operative/tourniquet times, blood loss, wound complications, and did not eliminate the need for syndesmosis fixation.

Influence of posterior malleolar fragment morphology on the outcomes of trimalleolar fractures: A systematic review and meta-analysis

BACKGROUND

Trimalleolar fractures are generally considered to have inferior outcomes among ankle injuries. Historically, emphasis was placed on the size of the posterior malleolar fracture (PMF) to guide surgical decision-making and predict outcomes. Recent studies have suggested that the morphology of the PMF fragment is more important than its size. The aim of this systematic review was to determine if the outcomes of trimalleolar fractures depend on the morphology of the PMF as per the Haraguchi classification system after surgical fixation.

METHODS

A systematic literature search was conducted in the electronic databases of PubMed, Embase, Scopus, and Ovid. Title and abstracts were screened, and data from eligible studies were extracted. Meta-regression and pooled analysis was performed using appropriate computer software.

RESULTS

11 studies with 597 patients were included in the final analysis. Pooled mean AOFAS score was 87.43 (95% CI 84.24-90.62) after a mean follow-up of 31.6 months. Univariate and multivariate meta-regression analysis demonstrated that as the percentage of Haraguchi type 1 patients increased, there was a statistically significant improvement in outcome scores. A similar trend was noted for Haraguchi type 3 fractures, and a reverse trend was observed for Haraguchi type 2 injuries, although neither were statistically significant.

CONCLUSION

Our review suggests that the outcomes of trimalleolar fractures after surgical fixation may depend on the morphology of the PMF, with Haraguchi type 1 fractures having overall superior functional outcomes than Haraguchi type 2 and 3 injuries. Future studies need to done to conclusively prove or refute these findings.

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.

[Established classification systems of posterior malleolar fractures : A systematic literature review]

BACKGROUND

Posterior malleolar fractures are found in almost 50% of all ankle fractures. The high clinical relevance of these joint fractures is explained by the significantly worse clinical and functional outcome. There is still a lack of unified opinion regarding the classification and treatment of these fractures.

OBJECTIVE

The aim of this article is to provide a systematic literature review of clinical studies that investigated posterior malleolar fractures and classified them using one of the three established classifications according to Haraguchi, Bartonicek/Rammelt, or Mason.

MATERIAL AND METHODS

PubMed was searched without time limits. 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 27 studies with a total of 2220 patients were included in this systematic literature review. Trimalleolar fractures showed a significantly less favorable prognosis than other ankle fractures. The quality of reduction was the most important prognostic factor for the clinical outcome.

CONCLUSION

None of the three classifications examined has become established in the literature. Most of the classifications are weak or should not be used with respect to a derivable treatment algorithm or a prognosis with respect to the outcome. Only the classification according to Bartonicek/Rammelt is suitable to become established in the literature and in clinical practice due to its derivable treatment algorithm.

Percutaneous Fixation of Posterior Malleolar Fractures in Patients With Unstable Ankle Fractures Treated With a Fibular Intramedullary Nail: A Description of a Technique and Review of Outcomes

OBJECTIVES

To (1) describe the percutaneous technique used to reduce and fix a posterior malleolar fracture with anteroposterior screws in patients managed with a fibular intramedullary nail, (2) describe the selection of patients to whom this technique can be applied, and (3) report the clinical and patient reported outcome of this intervention.

DESIGN

Retrospective review.

SETTING

Academic orthopaedic trauma center.

PATIENTS

Thirty-two consecutive patients with a mean age of 65 years (range, 39-90) over a thirteen-year period identified from a prospective database.

INTERVENTION

Unstable ankle fractures managed surgically with a fibular nail and percutaneous fixation of the posterior malleolar component.

MAIN OUTCOME MEASUREMENTS

The primary short-term outcome was complications related to posterior malleolar fracture fixation. The primary mid-term outcome was the Olerud-Molander Ankle Score. Secondary outcomes included the Manchester-Oxford Foot Questionnaire, EuroQol-5D, health, pain, and satisfaction.

RESULTS

Thirty of the 32 (94%) posterior malleolar fractures united uneventfully. Postoperative loss of talar reduction occurred in 2 patients (6.3%), which in 1 patient (3.1%) eventually required a hindfoot nail arthrodesis. There were no soft-tissue complications related to the anteroposterior screws or the fibular nail fixation. At a mean follow-up of 3.7 years (range, 1-8), the median Olerud-Molander Ankle Score, Manchester-Oxford Foot Questionnaire, EuroQol-5D, health, pain, and satisfaction scores were 80.0, 23.4, 0.85, 80.0, 85.0, and 87.5, respectively.

CONCLUSIONS

Percutaneous ankle fracture fixation with a fibular nail and posterior malleolar screws results in reliable fracture stabilization, good patient outcomes, and high treatment satisfaction.

LEVEL OF EVIDENCE

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

Isolated Posterior Malleolar Fracture: A Case Report of a Rare Presentation With Narrative Review of Literature

The isolated posterior malleolar fracture is a rare case. An innocuous injury may have associated ligamentous disruption. The fracture classification and treatment protocol are not well-defined. A missed injury results in poor functional outcomes.

A 28-year-old male sustained a twisting injury to his left ankle. The radiograph revealed an isolated posterior malleolar fracture. A computerized tomographic examination suggested talus lateralization and deltoid ligament injury. Surgical fixation with a syndesmotic screw was done. Post-operative delayed weight-bearing was allowed. At a one-year follow-up, there was painless weight-bearing and independent mobilization.

The posterior malleolus significantly contributes to ankle stability. The estimation of fragment size may be an erroneous guiding factor for surgical fixation. Recent literature suggests that syndesmotic stability, residual talus subluxation, joint congruence, and fibular notch involvement are more significant factors for risk assessment and to guide the management of posterior malleolar fracture.

The isolated posterior malleolar fracture presents rarely. They should be evaluated by tomographic evaluation and an unstable injury should be surgically managed.

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.

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

The Association Between Lateral Radiographs and Axial Computed Tomography of Posterior Malleolar Fractures as a Tool for Predicting Medial Malleolar Extension: A Multi-Center Retrospective Analysis

Posterior malleolar fractures are often part of complex ankle fracture patterns. Radiographs and computed tomography are often obtained in the preoperative setting. In this study, we compared measurements from lateral ankle radiographs with measurements on axial computed tomography. We hypothesize that there is an association between measurements taken on lateral XR and certain fracture morphology such as medial extension and that measurements taken on lateral XR can be used to predict likelihood of medial extension type fractures. A multi-center retrospective analysis was performed involving patients with trimalleolar ankle fractures treated at two large urban healthcare systems ranging from January 1, 2010 to November 1, 2019. A total of 279 patients met criteria including 186 females and 93 males aged 18 to 90 with an average age 55. Four reviewers measured continuous variables on lateral radiograph and axial computed tomography: posterior malleolus fracture height, articular surface length, medial-lateral width, and anterior-posterior depth and then agreement was assessed via intraclass correlation coefficient. Pearson correlations were calculated for all pairwise combinations of measurements. Two fracture classification systems were then evaluated for association with the continuous variables. Lateral height was divided into quartiles and analyzed for the degree of association. Positive correlation was found between lateral height and axial depth/axial width. Taller lateral height values were statistically associated with medial extension type fractures. Lateral height 24.5mm-29.5mm is 3.1x higher, and lateral height >29.5mm is 8.6x more likely to have medial extension when compared to shorter lateral heights(<20.5mm). Based on these findings we suggest increased usage of pre-operative CT and evaluation for the use of posteromedial approaches in the setting of taller lateral height fracture patterns(>24.5mm) as seen on lateral XR.

Defining a Safe Zone for Percutaneous Screw Fixation of Posterior Malleolar Fractures

Posterior malleolar fractures require fixation to confer stability to the ankle. Although some have suggested that fractures involving less than 25% of the articular surface require no intervention, estimation of malleolar size on plain imaging is inaccurate. Some posterior malleolar fractures may be particularly suitable for posterior-to-anterior percutaneous screw fixation of the posterior malleolus via a posterolateral approach. We hypothesized that there may be a safe zone in the posterolateral ankle, identifiable with reliable anatomic landmarks, that might allow safe percutaneous screw placement for fracture fixation. The study protocol involved Step 1, in which multiple Kirschner wires were used in a single cadaveric specimen to attempt to identify a safe zone entry point in the posterior ankle, and Step 2, in which a single wire was used in each of six additional cadaveric specimens to test the ability to safely replicate the use of that entry point. In Step 1, a safe zone entry point was identified, located immediately lateral to the Achilles tendon and 1 cm above the level of the tip of the medial malleolus, when visualizing the posterior ankle. In Step 2, using these landmarks and an image intensifier, single wires were then successfully placed in the other six specimens without injury to any significant structure. If confirmed in clinical studies, the safe zone entry point that we have identified could potentially be used to facilitate posterior-to-anterior percutaneous fixation in patients with posterior malleolar fractures for whom open reduction may not be required or may be contraindicated.

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.

Posterolateral Approach to Posterior Malleolar Fractures: A Literature Review

This study reviews the current evidence on the indications and outcomes of the posterolateral approach in the treatment of posterior malleolar fractures. PubMed and Google Scholar search engines were used to construct a review of the literature for all studies detailing the posterolateral approach for posterior malleolar fracture fixation. A total of 11 studies met our inclusion criteria. In total, 332 fractures were identified. Overall superficial infection occurred in 4.5%, skin necrosis in 4.5%, and nerve injury in 4.5%. Hardware irritation that required removal occurred in 13.6%. None of the hardware removals involved posterior malleolus fixation. A total of 51 (15.4%) cases of arthritis were reported, follow-up ranged from a mean of 5.3 months to a mean 7.9 years. Regardless the majority of patient reported outcomes were excellent/good at final follow-up. Thresholds for joint reduction were not uniformly described or even quantified at all in some of the included studies. Variable indications for fixation were reported without reference to posterior malleolus fracture morphology. The posterolateral approach provides a satisfactory approach for fracture reduction with similar complication rates to that reported for other ankle fracture approaches. Further research is required on posterior malleolus fracture morphology, optimal fracture fixation and longer term functional and radiological outcomes.Levels of Evidence: Level III: Systematic review of retrospective cohort studies.

Management of posterior malleolus fractures: A multicentre cohort study in the United Kingdom

BACKGROUND

There is a need to assess clinical practice in light of increasing literature recommending fixation of posterior malleolus (PM) fractures. This multicentre study examines treatment approaches, within both Major Trauma Centres and District General Hospitals and role of radiographs and CT scanning.

METHODS

Trauma lists and databases were used to identify patients and data collected from electronic and paper medical records and imaging systems between August 2017-18. Analysis of treatment and outcomes was then conducted.

RESULTS

One-hundred-and-sixty ankle fractures were included in the study, only 68 ankle fractures underwent CT scanning following initial radiographs and of these, 65 were managed operatively, with 32 undergoing PM fixation. Syndesmotic stabilisation was performed in 9.6% where the PM was fixed.

CONCLUSION

CT is still under-utilised, PM fractures that appear to be anything other than small avulsion-type injuries should undergo CT scanning. Syndesmotic stabilisation is statistically less likely to be performed with fixation of the PM.

Reconciliation Between Lateral X-ray and Axial Computed Tomography Regarding Posterior Malleolus Fracture Anatomy and Medial Malleolus Involvement: A Pilot Study

Configuration of a posterior malleolus fracture has significant variation based on mechanism of injury and concomitant ankle injuries. Radiographs obtained during early workup of ankle trauma play a pivotal role in closed reduction, surgical planning and preoperative management. Preoperative computed tomography helps distinguish fracture pathoanatomy. The purpose of this study is to relate measurements from traditional lateral radiographs with measurements on axial computed tomography. Imaging from a total of 22 patients treated at our institution from January 2008 to 2018 were evaluated. Two raters measured posterior malleolus fracture height and articular surface length on lateral radiographs, as well as medial-lateral width and anterior-posterior depth on axial computed tomography using calibrated imaging software. Posterior malleolar fractures with medial extension were recorded. Pearson correlations were calculated for all pairwise combinations of measurements. Lateral height and axial width were positively correlated. There was found to be an association between taller lateral height, and separately, wider axial width with presence of medial extension. Based on the correlations found between the measurements as well as the independent associations found with presence of medial extension, we suggest posterior-medial incision be evaluated as a potential approach in taller fractures as noted on lateral radiograph.

Traditional Approach vs Posterior Approach for Ankle Fractures Involving the Posterior Malleolus

BACKGROUND

In the past, posterior malleolus fragments (PMFs) commonly have been indirectly reduced and fixed when fragments involve 25% or more of the tibial articular surface, while smaller fragments were left unfixed. The posterior approach has become increasingly popular and allows fixation of even smaller fragments. This study compares clinical outcome for the 2 treatment strategies.

METHODS

Patients with ankle fractures involving a PMF treated from 2014 to 2016 were eligible for inclusion. Patients were allocated to group A (treated with a posterior approach) or group B (treated with the traditional approach) according to the treatment given. A one-to-one matching of patients from each group based on the size of the PMF was performed. Patient charts were reviewed, and outcome evaluation was performed clinically, radiographically, and by patient-reported outcome measures (PROMs; Self-Reported Foot and Ankle Score, RAND-36, visual analog scale [VAS] of pain, and VAS of satisfaction). Forty-three patients from each group were matched. Median follow-up was 26 (interquartile range [IQR], 19-35) months postoperatively.

RESULTS

The median PMF size was 17% (IQR, 12-24) in both groups, and they reported similar results in terms of PROMs. Fixation of the PMF was performed in 42 of 43 (98%) patients in group A and 7 of 43 (16%) patients in group B (P < .001). The former group more frequently got temporary external fixation (56% vs 12%, P < .01) and less frequently had syndesmotic fixation (14% vs 49%, P < .01), and they had less mechanical irritation and hardware removal but more noninfectious skin problems (28% vs 5%, P < .01). Median time from injury to definitive surgery (8 vs 0 days, P < .001) and median length of stay (12 vs 3 days, P < .001) were longer in group A.

CONCLUSION

Comparison of treatment strategies for ankle fractures involving the posterior malleolus showed similar results between patients treated with a traditional approach and a posterior approach.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Outcomes of posterior malleolar fixation in ankle fractures in a major trauma centre

AIMS

Ongoing controversy exists over the indications and benefits of posterior malleolar fixation in ankle fractures. The aim of this pragmatic study was to evaluate the outcomes of posterior malleolar fracture fixation in ankle fractures in the setting of a major trauma centre. Our hypothesis is that posterior malleolus fixation leads to improved clinical outcomes.

METHODS

A total of 320 patients were identified with operatively treated ankle fractures involving a posterior malleolus component, at our institution between January 2012 and January 2018, ensuring a minimum 2 year follow-up. Of these patients, 160 had the posterior malleolus fixed as part of their surgery and 160 did not. Patient demographics, surgical details and complications were assessed. The Manchester-Oxford Foot Questionnaire (MOXFQ) was the primary patient outcome measure.

RESULTS

Fixation of the posterior malleolus was associated with a statistically significant improvement in patient outcomes. Mean MOXFQ score in the unfixed posterior malleolus group was 24.03 (0 - 62), compared to 20.10 (0 - 67) in the fixed posterior malleolus group (p = 0.04). Outcomes were worse with increasing size of posterior malleolar fragment. Metalwork-related issues were higher in the posterior malleolus fixed group (24/160 (15%) versus 10/160 (6.2%)) and re-operation rate was double.

CONCLUSION

This study demonstrates that in the practical setting of a major trauma unit, fixation of the posterior malleolar fracture leads to improved patient outcomes but with increased metalwork risks and reoperation rates.

[Fracture of the posterior malleolus : A paradigm shift]

Ankle fractures with involvement of the posterior malleolus have a poor prognosis. The traditional concept of addressing the posterior fragment as the final step in the surgical reconstruction depending on the fragment size manifest in the lateral X‑ray, does not do justice to the anatomic and biomechanical relevance of the posterior malleolus. Intra-articular step-offs and fragment displacement ≥ 2 mm, impacted intercalary fragments, involvement of the fibular notch and instability of the syndesmosis, represent parameters relevant for the surgical reconstruction and the functional and radiomorphological outcome independent of fragment size. A valid assessment of these parameters can only be achieved via computed tomography (CT) including multiplanar 2D and 3D reconstruction. This is the foundation for the classification of posterior malleolar fractures according to Bartoníček et al., it forms the basis of the preoperative analysis of the fracture components and represents a decision-making tool for the indications for surgery. The individual fracture pattern guides the selection of the suitable approach or a combination of approaches and the surgical strategy. Making use of the posterior approaches enables the surgeon to have a direct view of the fracture components of the posterior malleolus as a precondition for an anatomic reduction. This central surgical step is frequently done as the first measure of the surgical reconstruction of the ankle joint. Furthermore, direct reduction and posterior stabilization is more accurate and stable than indirect reduction from an anterior approach with indirect fixation using lag screws. An additional temporary transfixation of the tibiofibular syndesmosis is often dispensable.

Posterior approaches to the ankle - an analysis of 3 approaches for access to the posterior malleolar fracture

BACKGROUND

An anatomical study to determine what degree of access to the posterior distal tibia could be gained by using 3 different approaches; the posterolateral, the posteromedial and the medial posteromedial approaches.

METHODS

A comparison study, between the anatomical dissection of 7 fresh frozen cadaveric lower legs and image analysis of CT data of posterior malleolar fractures from a prospectively collected database was conducted. All fractures have been classified using the Mason and Molloy classification.

RESULTS

In comparing the posterior malleolar fracture fragment width to distal tibia width, the posterolateral fragment encompasses 60.1% (95% CI 56.8, 63.3) of the total width of the tibia. If the posteromedial fragment is included the fragments encompass the entire distal tibia (100%). In type 3 fractures, 81.4% (95% CI 75.5, 87.1) of the distal tibia width is involved. When comparing the fracture width to the approach, no approach achieves a complete exposure of the type 2B or 3 fracture patterns. The overall surface area of the type 2B and 3 fractures, is significantly greater than all the approaches. Considering the lateral to medial extent of the fracture, the posterolateral fragment mean width is 33% greater than what can be exposed by the posterolateral approach (mean 24.9 vs 16.8mm). In type 2B and 3 fractures, the horizontal exposure reduces to 39.8% and 47.6% respectively. In comparison, the PM approach exposes 47.6% of the type 2B fracture pattern and 57.1% of the type 3 fracture pattern and allows a preferable angle for hardware insertion. The MPM approach does not expose any of the posterolateral fragments in this study, however it does expose 92% (mean 21.9 vs. 23.8mm) of the medial to lateral width of a posteromedial fragment of a type 2B fracture.

CONCLUSION

Each approach allows access to different parts and amounts of the posterior tibia. An understanding of and utilisation of these approaches can lead to adequate exposure for fixation of most posterior malleolus fracture patterns seen.

Clinical and radiological mid- to long-term results after direct fixation of posterior malleolar fractures through a posterolateral approach

BACKGROUND

Direct fixation of posterior malleolar fractures has been shown to lead to higher accuracy of fracture reduction compared to an indirect anterior to posterior fixation but lacks long-term clinical results. This study shows the mid- to long-term clinical and radiological outcome after direct fixation of the posterior malleolus through a posterolateral approach.

MATERIALS AND METHODS

Thirty-six patients with an ankle fracture including a posterior malleolar fragment (23 × AO-44C, 12 × AO-44B, 1 × unclassifiable) treated with direct fixation of the fragment through a posterolateral approach were retrospectively evaluated. There were 24 females (67%) with a mean age of 63 (range 34-80) years and a BMI of 28 (range 19-41) kg/m² at the time of surgery. An initial fracture-dislocation was seen in 67%. The clinical outcome was assessed with the Visual Analog Scale (VAS, 0-10 points) and the American Foot and Ankle Society (AOFAS, 0-100 points) score. Posttraumatic osteoarthritis was recorded with the Van Dijk Classification (grade 0-III). Subgroup analyses of patient- and fracture-associated risk factors (age, BMI, smoking, fracture-dislocation, postoperative articular step-off) were assessed to reveal possible negative prognostic predictors.

RESULTS

After a mean follow-up of 7.9 (range 3-12) years, the median VAS was 1 (IQR 0-2) point, and the median AOFAS score was 96 (IQR 88-100) points. Ankle range of motion measurements showed a significant, but clinically irrelevant, difference in plantar- and dorsiflexion between the affected and unaffected ankle. 92% of the patients were very satisfied or satisfied with the postoperative course. 89% had no preoperative signs of ankle osteoarthritis. Osteoarthritis progression was seen in 72%, with 50% showing grade II or III osteoarthritis at the final follow-up. No significant negative prognostic factors for a worse clinical outcome could be detected.

CONCLUSION

Direct fixation of posterior malleolar fractures through a posterolateral approach showed good clinical mid- to long-term results with a high satisfaction rate but substantial development of posttraumatic ankle osteoarthritis. Further studies should include CT analysis of the preoperative fracture morphology and even, perhaps, the postoperative reduction accuracy to evaluate the benefit of posterior malleolar fracture reduction in preventing ankle osteoarthritis in the long term.

LEVEL OF EVIDENCE

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

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.

Ankle stability in ankle fracture

Restoration of normal ankle kinematics should be the all-encompassing ethos in the approach to management of ankle fractures. To do this, the ligamentous stabilisers must also form part of its assessment and definitive management and be considered during index fracture fixation surgery. This article is a review of the anatomy, mechanics and clinical testing of instability in ankle fractures.