Posterior Malleolus Fractures

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.

A biomechanical comparison of posterior malleolar fracture fixation using screws and locking plates in Trimalleolar fractures: a finite element study

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Can Lateral X-Rays Reliably Determine Which Posterior Malleolus Ankle Fractures Need a CT?

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVELS OF EVIDENCE

Level III: Diagnostic.

Unstable Rotational Ankle Fractures Treated With Anatomic Mortise Repair and Direct Posterior Malleolus Fixation

Introduction: The purpose of this study was to evaluate patient outcomes following a standardized algorithmic approach to ankle mortise stabilization, following rotational fracture, utilizing direct repair of the posterior malleolus in the prone position. Methods: Eighty consecutive patients with unstable rotational ankle fractures that involved the posterior malleolus were analyzed. All underwent direct repair of the posterior malleolus regardless of size through a posterolateral approach. Electronic records were retrospectively reviewed for demographic information, initial injury and operation details, healing status, and complications. Preoperative and postoperative radiographs were obtained to assess the initial injury and healing was determined both by radiographic and clinical progress at follow-up visits. Results: Average posterior malleolus fragment width was 8.1 ± 3.7 mm (range = 2.1-19.9 mm) and percentage of the articular surface was 23.6% (range = 7.1%-56.7%) on the lateral radiograph. Overall, 80/80 (100%) patients healed their ankle fractures by a mean 2.9 ± 1.1 months. Only 1 (1.3%) patient required transsyndesmotic fixation following posterior malleolus repair. Mean range of ankle motion was as follows: dorsiflexion 20° ± 10°, plantarflexion 34° ± 10°, inversion 8° ± 4°, and eversion 7° ± 4°. Seventy-nine patients (98.8%) had an anatomic mortise reduction. Nine patients (11.3%) had a superficial wound complication, 3 patients (3.8%) had dysesthesia in the sural nerve distribution, and 1 patient (1.3%) lost reduction of the medial malleolus. Conclusion: Patients who undergo direct repair of the posterior malleolus in the prone position can expect a high rate of healing with superficial wound breakdown being the biggest problem, which was associated with an ankle fracture dislocation. Posterior malleolus fixation may obviate the need of transsyndesmotic stabilization.Levels of Evidence: Retrospective Level IV.

The morphometry of distal tibia and posterior malleolus and its clinical implications in total ankle prosthesis

PURPOSE

The aim of this study is to reveal the morphometry of the distal tibia and posterior malleolus and to generate morphometric reference data for the tibial component of total ankle prosthesis.

METHODS

This study was performed on 121 human dry tibiae (47 right, 74 left). The morphometric measurements of distal tibial structures, tibial length and the distance between the medial and posterior malleolus were measured in this study. Measurements on 44 tibiae were repeated three times and averaged for minimizing intra-observer error.

RESULTS

The tibial length was found 34.19 ± 2.31 cm. Mean values of width of fibular notch at tibial plafond and 10 mm proximal to the tibial plafond were 25.71 ± 2.44 mm and 17.81 ± 2.46 mm, respectively. Mean depth of fibular notch at tibial plafond and 10 mm proximal to the tibial plafond were 3.60 ± 1.04 mm and 3.37 ± 1.24 mm, respectively. Mean height of fibular notch was found 48.21 ± 10.51 mm. Mean width and height of medial malleolus were 25.08 ± 2.13 mm and 14.73 ± 1.85 mm, respectively. Mean width and length of tibial plafond were 27.71 ± 2.74 mm and 26.96 ± 2.62 mm, respectively. Mean values of width and height of posterior malleolus were measured 21.41 ± 3.26 mm and 6.74 ± 1.56 mm, respectively. Mean distance between medial and posterior malleolus was found 37.17 ± 3.53 mm. Mean width and depth of malleolar groove were 10.26 ± 1.84 mm and 1.73 ± 0.75 mm, respectively. The mean intra-class correlation values were found between the 0.959 and 0.999.

CONCLUSIONS

Knowing the distal tibial morphometry is crucial for designing convenient ankle replacement implants for Turkish population. To our knowledge, this study is the first in the literature that identifies posterior malleolar morphometry on dry tibiae. We believe that this study will make a significant contribution to the literature about distal tibial morphometry and especially the posterior malleolus and the data of our study can be used for designing total ankle prosthesis in Turkish population.

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.

Biomechanical insights into ankle instability: a finite element analysis of posterior malleolus fractures

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Plain X-ray is insufficient for correct diagnosis of tibial shaft spiral fractures: a prospective trial

PURPOSE

Tibial shaft spiral fractures and fractures of the distal third of the tibia (AO:42A/B/C and 43A) frequently occur with non-displaced posterior malleolus fractures (PM). This study investigated the hypothesis that plain X-ray is not sufficient for a reliable diagnosis of associated non-displaced PM fractures in tibial shaft spiral fractures.

METHODS

50 X-rays showing 42A/B/C and 43A fractures were evaluated by two groups of physicians, each group was comprised of a resident and a fellowship-trained traumatologist or radiologist. Each group was tasked to make a diagnosis and/or suggest if further imaging was needed. One group was primed with the incidence of PM fractures and asked to explicitly assess the PM.

RESULTS

Overall, 9.13/25 (SD ± 5.77) PM fractures were diagnosed on X-ray. If the posterior malleolus fracture was named or a CT was requested, the fracture was considered "detected". With this in mind, 14.8 ± 5.95 posterior malleolus fractures were detected. Significantly more fractures were diagnosed/detected (14 vs. 4.25/25; p < 0.001/14.8 vs. 10.5/25; p < 0.001) in the group with awareness. However, there were significantly more false positives in the awareness group (2.5 vs. 0.5; p = 0.024). Senior physicians recognized slightly more fractures than residents (residents: 13.0 ± 7.79; senior physicians: 16.5 ± 3.70; p = 0.040). No significant differences were demonstrated between radiologists and trauma surgeons. The inner-rater reliability was high with 91.2% agreement. Inter-rater reliability showed fair agreement (Fleiss-Kappa 0.274, p < 0.001) across all examiners and moderate agreement (Fleiss-Kappa 0.561, p < 0.001) in group 2.

CONCLUSION

Only 17% of PM fractures were identified on plain X-ray and awareness of PM only improved diagnosis by 39%. While experiencing improved accuracy, CT imaging should be included in a comprehensive examination of tibial shaft spiral fractures.

LEVEL OF EVIDENCE

II. Diagnostic prospective cohort study.

TRAIL REGISTRATION NUMBER

DRKS00030075.

Posterolateral approach for posterior malleolus fixation in ankle fractures: functional and radiological outcome based on Bartonicek classification

INTRODUCTION

Posterolateral approach has been advocated for the treatment of ankle fractures involving the posterior malleolus and satisfactory results were demonstrated in several studies. The Bartonicek classification based on 3-dimensional CT scanning was commonly used for treatment recommendation of posterior malleolar fracture (PMF). The aim of this retrospective study was to evaluate the clinical effect of the posterolateral approach for the treatment of PMF and present outcomes of patients with different types of Bartonicek classification.

METHOD

We retrospectively reviewed the clinical outcomes of 72 patients with ankle fractures involving posterior malleolus (PM) from January 2016 to December 2018. Posterior malleolus fractures (PMFs) were all directly reduced and fixed by a posterolateral approach using lag screws and/or buttress plates. AOFAS score and VAS pain score were used as the primary functional outcome measures. The radiographic evaluation included the quality of the reduction and Kellgren-Lawrence (KL) osteoarthritis classification. According to the CT-based Bartonicek classification, all patients were classified into three groups: 42 type II, 18 type III and 12 type IV. Bartonicek type II patients were further divided into subtype IIa 19 cases, subtype IIb 16 cases and subtype IIc 7 cases. The radiological and functional outcomes were analyzed among different types and subtypes of Bartonicek classification.

RESULTS

Sixty-eight patients (94.5%) achieved good or excellent reduction of PMF after surgery. The mean AOFAS score was 81.35 ± 6.15 at 6 months and 90.56 ± 4.98 at the final follow-up, respectively. The VAS score was 6.62 ± 1.03 one week after surgery, and 1.20 ± 0.92 at the final follow-up. Radiological evaluation at the final follow-up showed that primary bone union was achieved in all patients and 65 patients (88.9%) got no (KL grade 0) or just doubtable (KL grade 1) post-traumatic osteoarthritis. AOFAS scores decreased significantly with the severity of Bartonicek classification at 6 month (p < 0.001) and final follow-up (p < 0.05), while there was no statistical difference of VAS pain score among different types of Bartonicek classification. Reduction quality and the presence of osteoarthritis was not correlated to Bartonicek classification either. Besides, AOFAS scores at the final follow-up were statistically different among three subtypes of Bartonicek type II fractures (p < 0.05), and Bartonicek subtype IIa fractures had the highest AOFAS scores as 93 ± 4.99. Presence and severity of osteoarthritis was lower in patients with subtype IIa PMF compared to other subtype groups, this finding was statistically significant (p < 0.05).

CONCLUSION

The posterolateral approach could achieve good clinical outcomes in the treatment of posterior malleolus fracture. Patients with a Bartonicek type II fracture had a better functional outcome measured by the AOFAS score compared to other types. Bartonicek type IIa fractures got a higher AOFAS score and a lower incidence of osteoarthritis at the final follow-up than the other two subtypes. Classification of PMFs according to the Bartonicek classification was reliable.

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.

Open Reduction and Fixation of Lateral Malleolus and Syndesmosis for Ankle Re-Fracture

Rotational ankle fractures are often accompanied with a syndesmotic injury. Furthermore, malreduction of syndesmosis and fibular shortening are frequent errors observed in these cases and often lead to poor functional outcomes. We present a case of Weber C lateral malleolus fracture and distal tibiofibular syndesmotic injury in an active 23-year-old patient. Various techniques for syndesmotic reduction and restoration of fibular length are discussed and demonstrated.

Comparison of Two Surgical Approaches to Supination-External Rotation-Type Ankle Fractures

Objective

To compare the clinical outcome and postoperative complications of the treatment of supination-external rotation-type ankle fractures using the posterolateral approach in the prone position and the lateral approach in the supine position.

Methods

A retrospective cohort study was conducted in our hospital, including a total of 66 patients ranging from January 2013 to February 2016, regardless of age or sex. All the patients were classified as Lauge-Hansen supination-external rotation (SER)-type ankle fractures and were assigned to receive an open reduction and internal fixation (ORIF) through a posterolateral approach performed in the prone position (the "posterolateral approach group," 32 patients), or a lateral approach performed in the supine position (the "Lateral Approach Group," 34 patients). In the posterolateral approach group, 5 patients had Grade II fractures, 8 had Grade III fractures, and 19 had Grade IV fractures; among whom, 12 underwent fixation of the posterior malleolus with hollow screws and 6 with plates, and none of them had fixation of the distal tibiofibular syndesmosis; in the lateral approach group, 4 patients had Grade II fractures, 12 had Grade III fractures, and 18 had Grade IV fractures; among whom, 21 received fixation of the posterior malleolus, and 5 received fixation of the distal tibiofibular syndesmosis. The postoperative complications and ankle scores were recorded.

Results

After 1 year of follow-up, in the posterolateral approach group, the incision healed by primary intention and sutures were removed 2 weeks after the operation in all patients; 1 patient had pain in the region posterior to the fibula, presumably peroneal tendon irritation induced by internal fixation, which disappeared after fracture union and fixation device removal; no loosening or breakage of the internal fixation device was reported; the rate of good to excellent results was 96.8% at 12 months. In the lateral approach group: 1 case of wound infection, 1 case of necrosis of lateral skin flap, and 3 cases of lateral skin irritation were reported; the rate of good to excellent results was 94.6% at 12 months.

Conclusion

Compared with the traditional lateral approach, the posterolateral approach for the reduction and internal fixation of supination-external rotation-type ankle fractures performed in the prone position has more satisfactory clinical outcomes, with better reduction, more secure fixation, and smaller wound.

Establishment of a finite element model and stress analysis of intra-articular impacted fragments in posterior malleolar fractures

Background

Intra-articular impacted fragments (IAIFs) are considered articular surface fragments resulting from impact and compressive forces. The malreduction of IAIFs in posterior malleolar fractures has been associated with talar subluxation and long-term post-traumatic arthritis. In this study, we establish IAIF defect finite element models of different sizes in posterior malleolar fractures and explored how IAIF defects predict the onset of post-traumatic arthritis.

Methods

A reliable three-dimensional finite element model of the normal ankle was established. Finite element models with different sizes of IAIF defects were created to calculate ankle joint contact stress. The finite element data were recorded and analyzed.

Results

There was a linear relationship between the size of the IAIF defect and MCS with IAIF defects in the posterolateral region. The result of Pearson linear correlation analysis was r = 0.963, P = 0.009. The regression equation was MCS = 0.087*AI + 2.951 (AI, area of IAIF) by simple linear regression analysis. When the IAIF defect was in the posteromedial region, there was also a linear relationship between the size of the IAIF defect and MCS. The result of Pearson linear correlation analysis was r = 908, P = 0.033. The regression equation was MCS = 0.065*AI + 1.841. The MCS was increased mainly in the border of the IAIF defect.

Conclusions

A small IAIF defect in the posterior malleolus will result in a high MCS, and the MCS in the posterolateral region is larger than the MCS in the posteromedial region when the size of the IAIF defect is the same. We obtain the regression equation of MCS and area of IAIF defect. This indicates that patients are more prone to post-trauma arthritis when the size of IAIF defects is more than 17.8 mm² in the posterolateral region and more than 40.9 mm² in the posteromedial region.

Trial registration Retrospectively registered.

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.

Accompanying injuries in tibial shaft fractures: how often is there an additional violation of the posterior malleolus and which factors are predictive? A retrospective cohort study

Introduction

An undislocated fracture of the posterior malleolus is a common concomitant injury in tibial shaft spiral fractures. Nevertheless, these accompanying injuries cannot always be reliably assessed using conventional X-rays. Thus, the aim of the study is to evaluate how often a fracture of the posterior malleolus occurs with tibial shaft fractures (AO:42A/B/C and AO:43A) and which factors—identifiable in conventional X-rays—are predictive.

Methods

Retrospective evaluation of X-ray and CT images revealed a total of 103 patients with low-energy tibial shaft fractures without direct joint involvement. Proximal fractures and fractures involving the knee were excluded. Basic data on injury, the trauma mechanism, the path of the fracture, bony avulsions of the posterior syndesmosis and the procedures performed were evaluated.

Results

Thirty-nine fractures were located in the middle third of the tibia, 64 in the distal third. In 65 cases, a spiral fracture (simple or wedge fracture) was found. In 31/103 fractures, an additional osseous avulsion of the posterior syndesmosis could be detected, 5 (16.1%) of them were not recognized preoperatively due to an absence of CT imaging. In three of these patients, a fracture of the posterior malleolus was only recognized postoperatively, and an additional surgery was necessary. The spiral fractures were classified in the a.p. X-ray according to their path from lateral proximal to medial distal (Type A) or from medial proximal to lateral distal (Type B).

A Pearson chi-square test and Fisher’s exact test showed a highly significant accumulation of accompanying posterior malleolus fractures for type A fractures (p = 0.001), regardless of the location of the fracture. In addition, the fractures with involvement of the posterior malleolus had a significantly higher proportion in the fractures of the distal third (p = 0.003).

There was no statistically significant relationship between the height of the fracture and the path of the fracture (type A or B). These two factors seem to be independent factors for participation of the posterior malleolus.

Conclusion

In 40.6% of the tibial shaft fractures in the distal third, in 56.9% of the type A spiral fractures and in 67.6% of the type A fractures in the distal third, the ankle joint is involved with bony avulsion of the posterior syndesmosis, which is not always recognized in conventional X-rays. To avoid complications such as additional operations, instability and post-traumatic arthrosis, we recommend preoperative imaging of the ankle using CT for these fractures.

Level of evidence

III, retrospective cohort study.

Trail registration number

DRKS00024536.

The influence of size and comminution of the posterior malleolus fragment on gait in trimalleolar ankle fractures

BACKGROUND

Ankle fractures involving the posterior malleolus generally lead to worse outcome. However, no studies on gait in trimalleolar ankle fractures have evaluated the influence of size and comminution of the posterior malleolar fragment.

METHODS

We expected patients with more severely comminuted posterior malleolus, more severe fracture type and larger posterior fragment to have reduced gait kinematics and poorer patient-reported outcomes. 26 trimalleolar ankle fracture patients were compared with 14 healthy controls and kinematically analyzed using the Oxford Foot Model. Functional outcome was based on 4 patient reported outcome questionnaires. Effects of posterior fragment size, comminution and Haraguchi fracture classification were determined on conventional and 3D CT-scans.

FINDINGS

Trimalleolar patients had lower walking speed and reduced range of motion between the hindfoot and tibia in both loading and push-off phases in the sagittal and transverse planes. The range between the hindfoot and tibia in the sagittal plane in the push-off phase correlated significantly with patient reported outcomes. The absolute and relative surface area of the posterior fragment on conventional CT-scans and 3D CT-scans, correlated significantly with range of motion. Patients with a posterior malleolus size >10% of the posterior malleolus had lower flexion-extension between forefoot and hindfoot during loading phase than patients with a size ≤10%.

INTERPRETATION

Trimalleolar fractures reduce walking speed and range of motion in the talocrural joint. Reduced range in the talocrural joint is associated with poorer outcomes. Posterior fragment size correlated significantly with range of motion in talocrural and midfoot joints and with patient reported outcomes.

LEVEL OF EVIDENCE

Level 3, retrospective study.

Can treatment of posterior malleolus fractures with tibio-fibular instability be usefully addressed by Bartonicek classification?

INTRODUCTION

Ankle fractures account for 4% of all fractures and treatment of those involving the Posterior Malleolus remains controversial. Clinical and radiological outcomes in a cohort of patients with Posterior Malleolus fractures conservatively treated were retrospectively evaluated; furthermore, a treatment algorithm was suggested.

METHODS

Patients were divided according to Bartoníček classification. The clinical evaluation was made with OMAS/AOFAS scores; the radiological evaluation with Van Dijk classification for post-traumatic arthritis.

RESULTS

Clinical outcome worsened with the severity of Bartoníček classification, but early degenerative changes were not correlated neither to the clinical outcome nor to the injury pattern. Clinical and radiological outcomes depended on the damage of the syndesmosis as articular step-offs and tibio-fibular notch involvement.

DISCUSSION

We recommend conservative treatment for Bartoníček type I, type II and type III fractures, the latter when undisplaced and without tibial plafond depression. We suggest surgical treatment for type IV and displaced type III fractures.

Patient Pain and Function After Correction of Posterior Malleolar Malunion

BACKGROUND

The management of an ankle malunion involving the posterior malleolus remains challenging, and only a few published studies described the operative treatment of complex posterior malleolar malunion. A transfibular approach allows for direct visualization of the articular reduction of the posterior malleolus, but the reports of its use for correcting posterior malleolar malunion are rare. This study aims to evaluate the results of the intra-articular osteotomy via a transfibular approach for correcting an ankle malunion involving the posterior malleolus.

METHODS

We conducted a retrospective review of 26 patients with a symptomatic malunited ankle fracture involving posterior malleolus were treated with the intra-articular osteotomy via a transfibular approach in our department. Radiographic assessments were performed using plain radiographs and computed tomographic (CT) scans. Clinical outcomes were assessed using the AOFAS ankle-hindfoot score, visual analog scale (VAS), active range of motion of ankle, and the 36-Item Short-Form Health Survey score.

RESULTS

Postoperatively, anatomic correction of articular surface and anatomic reduction of syndesmosis were achieved in all patients as judged by CT scans. No evidence of progression had been found in 18 of 26 patients (69.2%) at final follow-up. The median AOFAS score improved from 42.0 to 81.5 (P < .001). Median pain VAS score decreased from 6.0 to 1.0 (P < .001). A favorable clinical outcome was associated with a short time interval from original injury to correction surgery and a lower grade of preoperative arthritis, but not with the posterior malleolar fragment size. However, time interval, the posterior malleolar fragment size, and the grade of preoperative arthritis showed no correlation with the progression of arthritis grade after surgery.

CONCLUSION

An intra-articular osteotomy via a transfibular approach demonstrated an improved function and pain after operative treatment of malunited ankle fracture with a displaced posterior malleolar fragment.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Clinical study of intramedullary nailing fixation for the treatment of Danis-Weber B in lateral malleolus fracture

OBJECTIVE

To compare the clinical effects between anatomical locking plates and interlocking intramedullary nails in patients with Danis-Weber B lateral malleolus fractures.

METHODS

This retrospective study enrolled patients with Danis-Weber B fractures of the lateral malleolus. All the operations were completed by the same group of surgeons. The reduction effect, operation time, intraoperative blood loss, hospital stay, fracture healing time and ankle functional outcomes (Olerud-Molander Ankle Score [OMAS]) were compared. Postoperative complications, including incision infections, fixation discomfort and internal fixation loosening, were also compared.

RESULTS

This study enrolled 73 patients that were treated with either an anatomical locking plate (locking plate group; n = 37) or an interlocking intramedullary nail (intramedullary nail group; n = 36). There was no significant difference between the two groups in terms of reduction effect, hospital stay and OMAS. The intramedullary nail group had significantly lower operation time, intraoperative blood loss and fracture healing time compared with the locking plate group. Postoperative complications in the intramedullary nail group were significantly lower compared with the locking plate group.

CONCLUSION

Using intramedullary nails resulted in more satisfactory functional outcomes compared with using locking plates in patients with Danis-Weber B fractures of the lateral malleolus.

Prognostic value of the Haraguchi classification in posterior malleolar fractures in A0 44-C type ankle fractures

BACKGROUND AND PURPOSE

Incidence of posterior malleolar fractures (PMFs) associated with ankle fractures is historically based on plain radiographs. Several classification systems for PMF are currently in use, but the reliability of the Haraguchi classification is not reported. The aim of this diagnostic cohort study was to assess incidence of PMF in patients with AO 44-C fractures, and test the reliability of the Haraguchi fracture classification based on CT. In addition, to evaluate the clinical outcome in patients with PMF.

METHODS

210 patients with an AO 44-C type fracture treated with syndesmotic fixation between 2011 and 2017 were included. Presence of PMF was registered, morphology was assessed and classified according to the Haraguchi classification. Interobserver agreement for the Haraguchi classification was evaluated. Patient assessment was conducted at 6 weeks, 6 months, 1 and 2 years. The American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Score (AOFAS) was the primary outcome measure. Secondary outcome measures included presence of osteoarthritis.

RESULTS

125 of 210 patients (60%) had a PMF. 34% of the PMFs were missed on plain radiographs compared to CT. The interobserver agreement was 0.797, (95% CI: 0.705 to 0.889, p < 0.001), for the Haraguchi classification. The 2-year follow-up rate was 86%. Haraguchi type II fractures had a lower AOFAS compared with the no-fracture group at 6 weeks (mean difference -7.5 (95% CI; -15.0 to -0.2), p = 0.04) and 6 months (mean difference -8.4 (95% CI; -15.3 to -1.5), p = 0.01). Presence of osteoarthritis was higher in patients with Haraguchi type II PMF compared to the no PMF group, this finding was not significant (relative risk (RR) 1.6(95% CI 1.1 to 2.4, p = 0.059)).

CONCLUSIONS

Plain radiographs underestimated PMF. Patients with a Haraguchi type II fracture had a poorer outcome measured by the AOFAS score compared to no PMF up until 6 months. Classification of PMF according to the Haraguchi classification was reliable.

[Comparison of the effectiveness of the posterior malleolus fixed or not on treatment of different Haraguchi's classification of posterior malleolus fractures]

Objective

To investigate the effectiveness of fixation the posterior malleolus or not to treat different Haraguchi's classification of posterior malleolus fractures.

Methods

The clinical data of 86 trimalleolar fracture patients who were admitted between January 2015 and September 2019 and met the selection criteria were retrospectively reviewed. There were 29 males and 57 females; the age ranged from 26 to 82 years with a mean age of 55.2 years. According to Haraguchi's classification, 38 patients were in type Ⅰ group, 30 patients in type Ⅱ group, and 18 patients in type Ⅲ group. There was no significant difference in the general data such as gender, age, and fracture location among the 3 groups ( P>0.05). The fixation of the posterior malleolus was performed in 23, 21, and 5 patients in type Ⅰ, Ⅱ, and Ⅲ groups, respectively. The operation time, fracture healing time, full weight-bearing time, postoperative joint flatness, and joint degeneration degree of the patients in each group were recorded and compared. The American Orthopedic Foot and Ankle Society (AOFAS) ankle and hindfoot score was used to evaluate ankle function, including pain, quality of daily life, joint range of motion, and joint stability. The AOFAS scores were compared between fixation and non-fixation groups in each group.

Results

The procedure was successfully completed by all patients in each group, and there was no significant difference in operation time ( F=3.677, P=0.159). All patients were followed up 12-36 months with a mean time of 16.8 months. At last follow-up, 6 patients were found to have suboptimal ankle planarity, including 2 patients (5.3%) in the type Ⅰ group and 4 patients (13.3%) in the type Ⅱ group, with no significant difference between groups ( χ ²=6.566, P=0.161). The ankle joints of all the patients in each group showed mild degeneration; the fractures all healed well and no delayed union or nonunion occurred. There was no significant difference in the fracture healing time and full weight-bearing time between groups ( P>0.05). No complications such as incision infection, fracture displacement, or plate screw loosening and fracture occurred during follow-up. At last follow-up, the total scores and pain scores of the AOFAS scores in the type Ⅱ group were significantly lower than those in the type Ⅰand Ⅲ groups ( P<0.05), there was no significant difference between groups in the scores for the quality of daily life, joint range of motion, and joint stability between groups ( P>0.05). There was no significant difference in any of the scores between the unfixed and fixed groups, except for the pain and quality of daily life scores, which were significantly lower ( P<0.05) in the unfixed group of type Ⅱ group than the fixed group.

Conclusion

Haraguchi type Ⅱ posterior malleolus fractures have a worse prognosis than types Ⅰ and Ⅲ fractures, especially in terms of postoperative pain, which can be significantly improved by fixing the posterior malleolus; the presence or absence of posterior malleolus fixation in types Ⅰ and Ⅲ has less influence on prognosis.

[Comparison of effectiveness between plate and screw internal fixation in treatment of posterior malleolus fractures through posterolateral approach]

Objective

To compare the effectiveness of posterior malleolus fractures treated by plate and screw internal fixation through posterolateral approach.

Methods

The clinical data of 95 patients with posterior malleolus fractures who were admitted between January 2016 and December 2019 and met the selection criteria were retrospectively analysed. They were divided into plate group (44 cases, treated with posterolateral plate internal fixation) and screw group (51 cases, treated with posterolateral screw internal fixation) according to different treatment methods. There was no significant difference in general data between the two groups of patients such as age, gender, cause of injury, side of injury, ankle fracture or injury classification, time from injury to operation, and percentage of posterior ankle fracture area to the distal tibia articular surface ( P>0.05). The operation time, hospital stay, fracture healing time, and surgical complications were compared between the two groups. Imaging examinations (X-ray film, CT scan and reconstruction) were used to assess the reduction quality of ankle fracture, articular congruity, and re-displacement in ankle fracture. At last follow-up, the pain visual analogue scale (VAS) score was used to evaluate the patients' pain, and the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was used to evaluate ankle joint function.

Results

Patients in both groups were followed up 6-30 months, with an average of 18.2 months. The operation time of the plate group was significantly longer than that of the screw group ( U=-2.040, P=0.041); there was no significant difference in hospital stay between the two groups ( U=-1.068, P=0.285). Incision swelling occurred in 2 cases in the plate group, sural nerve injury in 3 cases, and traumatic arthritis in 2 cases during follow-up. In the screw group, there were 1, 2, and 2 cases, respectively. The incidence of complications in the two groups (15.9% vs. 9.8%) was not significantly different ( P=0.372). All patients who underwent tibiofibular screw fixation underwent the removal of the tibiofibular screw before taking full weight bearing at 12 weeks after operation, and there was no screw fracture and retention. During the follow-up, there was no infection, re-displacement of fracture, delayed bone union or nonunion, and there was no significant difference in fracture healing time between the two groups ( t=0.345, P=0.731). There was no significant difference between the two groups of reduction quality of ankle fracture and articular congruity evaluation results ( P>0.05). At last follow-up, there was no significant difference in VAS score, AOFAS ankle-hindfoot score and evaluation grade between the two groups ( P>0.05).

Conclusion

Both the plate and screw internal fixation through posterolateral approach can achieve satisfied effectiveness in the treatment of posterior ankle fractures with maintenance of fracture reduction, and recovery of ankle joint function. The screw internal fixation has the advantages of minimal invasion and shorter operation time.

Posterior malleolar ankle fractures

AIMS

The primary aim of this study was to address the hypothesis that fracture morphology might be more important than posterior malleolar fragment size in rotational type posterior malleolar ankle fractures (PMAFs). The secondary aim was to identify clinically important predictors of outcome for each respective PMAF-type, to challenge the current dogma that surgical decision-making should be based on fragment size.

METHODS

This observational prospective cohort study included 70 patients with operatively treated rotational type PMAFs, respectively: 23 Haraguchi Type I (large posterolateral-oblique), 22 Type II (two-part posterolateral and posteromedial), and 25 (avulsion-) Type III. There was no standardized protocol on how to address the PMAFs and CT-imaging was used to classify fracture morphology and quality of postoperative syndesmotic reduction. Quantitative 3D-CT (Q3DCT) was used to assess the quality of fracture reduction, respectively: the proportion of articular involvement; residual intra-articular: gap, step-off, and 3D-displacement; and residual gap and step-off at the fibular notch. These predictors were correlated with the Foot and Ankle Outcome Score (FAOS) at two-years follow-up.

RESULTS

Bivariate analyses revealed that fracture morphology (p = 0.039) as well as fragment size (p = 0.007) were significantly associated with the FAOS. However, in multivariate analyses, fracture morphology (p = 0.001) (but not fragment size (p = 0.432)) and the residual intra-articular gap(s) (p = 0.009) were significantly associated. Haraguchi Type-II PMAFs had poorer FAOS scores compared with Types I and III. Multivariate analyses identified the following independent predictors: step-off in Type I; none of the Q3DCT-measurements in Type II, and quality of syndesmotic reduction in small-avulsion Type III PMAFs.

CONCLUSION

PMAFs are three separate entities based on fracture morphology, with different predictors of outcome for each PMAF type. The current debate on whether or not to fix PMAFs needs to be refined to determine which morphological subtype benefits from fixation. In PMAFs, fracture morphology should guide treatment instead of fragment size. Cite this article: Bone Joint J 2020;102-B(9):1229-1241.

A Retrospective Study on the Morphology of Posterior Malleolar Fractures Based on a CT Scan: Whether We Ignore the Importance of Fracture Height

Objective

The aim of this study was to investigate the respective correlation between the height (H) of a posterior malleolar fracture (PMF) and the involved area (S) of an articular surface and the presence of “die-punch.”

Methods

Patients with closed posterior malleolar fractures admitted to our hospital from January 2015 to December 2017 were selected, with complete X-ray and 3D reconstruction CT imaging data. The gender, age, injured side, and surgical fixation methods of the patients were recorded. A preoperative ankle CT scan was performed, and the images were viewed through the PACS (Picture Archiving and Communication Systems). Simultaneously, the involved joint surface area (S) by the posterior malleolar fracture was measured, as well as the proportion of the fracture area to the total ankle joint area. On the sagittal reconstruction CT images, the height (H) of the posterior malleolar fracture was measured to compare the correlation between the height of the fracture and the area of the fracture, as well as the area ratio. Besides, according to the presence or absence of “die-punch,” patients were divided into two groups: A and B. And each group was further divided into three subgroups according to age (16-39 years old, 40-59 years old, and ≥60 years old). The statistical differences in the height of fracture between the subgroups were compared.

Results

A total of 48 patients, aged 16-82 years, with an average age of 48.9 years, were included in this study, including 13 males and 35 females. There were 20 cases of left ankle injury and 28 cases of right ankle injury. The average height of the posterior malleolar fractures was 18.19 mm, the average area of the fracture was 202.28 mm², and the average ratio of the fracture area to the total articular surface area was 17.84%. Besides, die-punch was seen in 27 cases and not in 21 cases. The average height of fractures was 21.33 ± 5.38 mm in group A1, 14.38 ± 9.01 mm in group B1, 18.30 ± 7.95 mm in group A2, 14.48 ± 5.37 mm in group B2, 26.26 ± 6.73 mm in group A3, and 12.77 ± 3.07 mm in group B3.

Conclusion

The height (H) of the posterior malleolar fractures is positively correlated with the fracture area (S) and the fracture area ratio (FAR). The posterior malleolar fractures with “die-punch” tend to have a greater average height than that without “die-punch.” In clinical work, orthopedic surgeons should not only pay attention to the size of the posterior malleolus fracture but also value its height, which hopefully could provide insight into the treatment and prognosis of PMF patients.

Arthroscopically Assisted Treatment of Complex Ankle Fractures: Intra-articular Findings and 1-Year Follow-Up

Especially after complex ankle fractures, patients regularly suffer from residual symptoms, presumably due to occult intra-articular injuries. The aim of this study was to evaluate the intra-articular lesions, identify fractures specifically at risk for these, and assess the results after arthroscopically assisted open reduction and internal fixation of complex ankle fractures after 1 year. The primary outcome was the American Orthopedic Foot and Ankle Society (AOFAS) hindfoot score. Secondary outcome parameters were the Olerud and Molander Ankle Score (OMAS), Tegner activity scale, arthroscopic findings, functional assessment, and complications. Thirty-two patients (56% female) were enrolled. Chondral lesions were detected in 91%. Full-thickness lesions treated by microfracturing were observed in 0% of unimalleolar, 43% of bimalleolar, and 40% of trimalleolar fractures. After 1 year, the median (interquartile range) AOFAS was 94 (9) and OMAS was 90 (10) for all patients. When analyzing factors possibly influencing the outcome, age, sex, smoking, grading for surgical procedures according to the American Society of Anesthesiologists, fracture type (uni-, bi-, or trimalleolar), severity of chondral lesions graded according to the International Cartilage Repair Society (grade <4 versus grade 4), and syndesmotic instability had no significant influence on the outcome. The only variable significantly influencing the AOFAS (p = .004) and OMAS (p < .001) was body mass index (BMI; r_s = -0.522 and -0.606, respectively), with a higher BMI resulting in inferior outcome scores. Complications were observed in 3 patients, 2 with superficial skin necrosis at the posterolateral incision and 1 nonunion of the medial malleolus. Taken together, these data show that intra-articular injuries were common in ankle fractures. Bi- and trimalleolar fractures were particularly at risk for full-thickness lesions. A higher BMI tended to result in inferior outcome scores. Arthroscopically assisted open reduction and internal fixation led to good to excellent results in all but 1 patient.

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.

Finite element analysis of the effect of sagittal angle on ankle joint stability in posterior malleolus fracture: A cohort study

OBJECTIVE

Aim of this study was to establish three-dimensional finite element model of the posterolateral-oblique type of posterior malleolus fracture with different sagittal angle and to explore the effect of sagittal angle on ankle joint stability.

METHODS

CT data of ankle were collected from a normal male volunteer.Established finite element model of the normal ankle and verified its reliability. Five posterior malleolus fracture models with different sagittal angles were established. Finite element analysis(FEA)was carried out to simulate the conditions of vertical loading in neutral position with a total weight of 600 N.Recorded the data and did statistical analyses.

RESULTS

(1) The contact area was 483.55 mm2 and the maximum contact stress was 3.793 MPa in the model of the normal ankle joint. (2) There was a positive correlation between the sagittal angle(SA)and the contact area(CA)(r = 0.925,P < 0.05). Regression equation was CA = 316.755 + 1.749* SA. The correlation between the sagittal angle and the maximum contact stress(MCS)was negative (r = -0.988,P < 0.01). Regression equation was MCS = 5.214-0.018*SA. There was a negative correlation between the sagittal angle of fracture and relative displacement(RD)(r = -0.950,P < 0.05). Regression equation was RD = 1.388-0.009*SA.

CONCLUSION

The greater the sagittal angle of fracture was, The more stable the ankle joint was. The sagittal angle of fracture could be used as a relative index to reflect ankle stability for posterior malleolus fracture.

Negative prognostic factors in surgical treatment for trimalleolar fractures

PURPOSE

Trimalleolar fractures are a common injury of the ankle that require surgical treatment to obtain an anatomic reduction of both malleoli and stabilization of the syndesmosis. This study aims to report the outcomes of surgical treatment for trimalleolar fractures, identifying the risk factors determining a worse result.

MATERIALS AND METHODS

Between January 2013 and December 2016, 48 patients with trimalleolar fracture treated with open reduction and internal fixation were retrospectively analyzed. The mean age was 44.69 years, and average body mass index (BMI) was 29.04. According to the Danis-Weber classification, 30 (62.5%) fractures were type B and 18 (37.5%) were type C. Clinical and radiographic evaluations at 3, 6, and 12 months were assessed. The functional results of Visual Analogue Staircases and Olerud-Molander (O&M) ankle score were reported.

RESULTS

No significant difference was found among the size of the PM in patients with and without ankle dislocation (p = 0.364). Therefore, there is no correlation between the size of the posterior fragment and the ankle dislocation and the size of the posterior malleolus and syndesmosis stability (p = 0.328). Age over 61 years, BMI > 40, ASA > 1, type C fracture, and fracture dislocation were considered as negative prognostic fractures.

CONCLUSIONS

Surgical treatment for trimalleolar fractures needs accurate preoperative planning. Age over 61 years, BMI > 40, ASA > 1, type C fracture, and fracture dislocation were considered as negative prognostic fractures.

Quantification of Postoperative Posterior Malleolar Fragment Reduction Using 3-Dimensional Computed Tomography (Q3DCT) Determines Outcome in a Prospective Pilot Study of Patients With Rotational Type Ankle Fractures

OBJECTIVE

To correlate Q3DCT measurements of residual step-off, gap, and 3D multidirectional displacement of postoperative posterior malleolar fracture fragment reduction in patients with rotational type ankle fractures, with patients' clinical outcome using standardized patient- and physician-based outcome measures.

DESIGN

Prospective cohort study.

SETTING

Level-I Trauma Center.

PATIENTS

Thirty-one patients with ankle fractures including a posterior malleolar fracture (OTA/AO type 44) were included.

INTERVENTION

All patients underwent open reduction internal fixation of their ankle fracture, of which 18 patients (58%) had direct fixation of the posterior malleolar fragment. Decision of (direct) fixation of the posterior malleolar fragment was not standardized and guided by surgeons' preference.

MAIN OUTCOME MEASUREMENTS

Quality of postoperative reduction was quantified using Q3DCT: posterior fragment size (% of joint surface), residual step-off (mm), postoperative gaps (mm), and overall multidirectional displacement were quantified. Foot and Ankle Outcome Score pain and symptoms subscales and quality of life (Short Form-36) at 1 year postoperatively were included as the main outcome measures.

RESULTS

Step-off (mean 0.6 mm, range 0.0-2.7, SD 0.8) showed a significant correlation with worse Foot and Ankle Outcome Score pain and symptoms subscales. Residual fracture gap (mean 12.6 mm, range 0.0-68.8, SD 19.5) and 3D multidirectional displacement (mean 0.96 mm, range 0.0-2.8, SD 0.8) showed no correlation.

CONCLUSIONS

In patients with rotational type ankle fractures involving a posterior malleolar fracture, contemporary Q3DCT measurements of posterior fragment size and residual intra-articular step-off-but not gap-show significant correlation with patient-reported pain and symptoms.

LEVEL OF EVIDENCE

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

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.

Open reduction and internal fixation of the posterior malleolus fragment frequently restores syndesmotic stability

AIM

Comparison of unfixed, CRIF, and ORIF of the posterior malleolus fragment (PMF) regarding the frequency of trans-syndesmotic fixation and quality of reduction in trimalleolar (equivalent) fractures.

MATERIAL AND METHODS

Retrospective registry study. Patients with a trimalleolar (equivalent) ankle fractures were identified within the departments' fracture database. General demographics, treatment details, and fracture specific details (CT-scans) were assessed. Patients were grouped per the PMF treatment: not addressed, CRIF, ORIF.

RESULTS

236 patients (53.0 ± 18.3 (range: 18-100) years), 58.1% female were eligible. The mean size of the PMF was 21.4 ± 10.4% (range: 2.7-55.9%), 71.6% were ≤25% of the tibial plafond. PMF fixation: Untreated 48.3%, CRIF 18.6%, ORIF 33.1%. ORIF of the PMF significantly (p < 0.001) reduced the frequency of trans-syndesmotic fixation (25%) compared to CRIF (61%) or untreated PMF (63%) with no significant influence of the PMF size (≤25%/>25%). ORIF resulted in a significantly (p < 0.001) better quality of reduction (1.2 ± 1.1 mm (range: 0-5 mm)) compared to CRIF (2.5 ± 2.1 mm (range: 0-8 mm)) and untreated PMF (2.5 ± 2.3 mm (range: 0-20 mm)). Neither the frequency of trans-syndesmotic fixation nor the quality of reduction differed significantly between untreated PMF and CRIF.

CONCLUSION

All posterior malleolus fragments, independent of their size, should be treated by ORIF, as this restores syndesmotic stability significantly more often than untreated PMF or CRIF.

Operative Management of AO Type 44 Ankle Fractures: Determinants of Outcome

The consequences of inadequate treatment of ankle fractures can be disastrous. We assessed the radiologic and functional outcomes, postoperative quality of life (QOL), and its determinants for patients treated operatively for AO type 44 ankle fractures. Evidence is lacking concerning the management of posterior malleolus fractures and syndesmotic injuries. Our retrospective adult cohort study included 432 AO/OTA type 44 ankle fractures (431 patients). The median follow-up period was 52 months. Outcomes were assessed from the medical records, radiographs, American Orthopaedic Foot and Ankle Society (AOFAS) ankle scale (functional outcome), and EuroQol EQ-5D questionnaires. The median AOFAS scale score was 88; 27.9% of patients reported restricted mobility and 40.4% pain or discomfort. In 8.8%, radiographic failure was observed. The presence of posterior malleolus fractures was significantly associated with poor functional outcomes, and a postoperative step-off correlated with radiologic failure, poor functional outcome, and poor postoperative QOL. Late syndesmotic screw removal was associated with worse EQ-5D time trade-off QOL scores. A substantial number of patients experienced functional impairment, discomfort, and pain. Syndesmotic injury was associated with ankle joint failure and poor functional outcomes. Our data indicate that all displaced posterior malleolus fracture fragments affecting the posterior articular tibial surface in patients aged ≤65 years require anatomic reduction.

Posterior malleolus fractures

The posterior malleolus component of a fracture of the ankle is important, yet often overlooked. Pre-operative CT scans to identify and classify the pattern of the fracture are not used enough. Posterior malleolus fractures are not difficult to fix. After reduction and fixation of the posterior malleolus, the articular surface of the tibia is restored; the fibula is out to length; the syndesmosis is more stable and the patient can rehabilitate faster. There is therefore considerable merit in fixing most posterior malleolus fractures. An early post-operative CT scan to ensure that accurate reduction has been achieved should also be considered.

Cite this article: Bone Joint J 2017;99-B:1413–19.