Is Incisura Fibularis a Reliable Landmark for Assessing Syndesmotic Stability? A Systematic Review of Morphometric Studies

In Different Gender Groups, What Is the Impact of the Fibular Notch on the Severity of High Ankle Sprain: A Retrospective Study of 360 Cases

OBJECTIVES

The role of the distal tibiofibular ligament in the occurrence of high ankle sprain (HAS) has been widely studied. But previous studies have overlooked the physiological and anatomical differences between males and females and have not further refined gender. Therefore, the impact of the anatomical morphology of fibular notch (FN) on HAS in different genders is still unclear. This study aimed to explore the impact of different types of FN on the severity of HAS and to estimate the prognosis of patients with HAS while excluding anatomical differences caused by gender.

METHODS

One hundred and eighty patients with HAS were included in this study as the experimental group (i.e., HAS group). They were further divided into four groups according to gender and FN depth, with deep concave FN ≥ 4 mm and shallow flat FN < 4 mm. Another 180 normal individuals were set as the control group. The FN morphological indicators, tibiofibular distance (TFD), and ankle mortise indexes were measured and compared with those in HAS group. The independent t-test was used to compare continuous variables between groups, the intraclass correlation coefficient (ICC) was used to analyze the reliability of intra-observer measurement, and the Pearson correlation coefficient was used to verify the correlation between FN and the severity of HAS.

RESULTS

In males with shallow flat type, the measurements of anterior tibiofibular distance (aTFD), middle tibiofibular distance (mTFD), posterior tibiofibular distance (pTFD), front ankle mortise width (fAMW), middle ankle mortise width (mAMW), posterior ankle mortise width (pAMW), and depth of ankle mortise (DOAM) in HAS group were significantly larger than those in normal group (p < 0.05). In male patients with deep concave type, the measurements of aTFD, mTFD, fAMW, mAMW, and DOAM were significantly larger than those in normal group (p < 0.05). Among female patients with shallow flat type, the measurements of aTFD, mTFD, pTFD, fAMW, mAMW, pAMW, and DOAM were found to be significantly larger than those in normal group (p < 0.05). Among female patients with deep concave type, the measurements of mTFD, pTFD, fAMW, mAMW, and DOAM were found to be significantly larger than those of the normal group (p < 0.05). The depth of FN was negatively correlated with TFD, and the AOFAS score of patients with shallow flat type was significantly lower than that of patients with deep concave type after treatment (p < 0.05).

CONCLUSIONS

In different gender groups, compared with the normal controls, the TFD and partial ankle mortise indices were significantly different in HAS patients. Moreover, FN depth was negatively correlated with TFD, and the AOFAS score of shallow flat patients was significantly lower than that of deep concave patients. These suggested that shallow flat FN may be associated with more severe distal tibiofibular ligament injury and ankle mortise widening, leading to poorer prognosis. This should be taken seriously in clinical practice.

Revision Strategies for the Aseptic, Malaligned, Surgically Treated Ankle Fracture

Although surgical fixation can take many forms depending on ankle fracture morphology, the goals of open reduction internal fixation are to restore fracture alignment, re-establish ankle stability, and achieve an anatomic mortise. A subset of patients may present postoperatively with evidence of suboptimal open reduction internal fixation. Increased contact pressures across the tibiotalar joint, increased talar shift, and pathologic joint loading leading to the development of post-traumatic arthritis are common sequela of the malaligned mortise. Treatment necessitates a comprehensive approach. This article describes our preferred systematic approach for diagnosis and treatment of the aseptic, malaligned, surgically treated ankle fracture.

Imaging Techniques for Assessment of Dynamically Unstable Sports Related Foot and Ankle Injuries

Foot and ankle instability can be seen both in acute and chronic settings, and isolating the diagnosis can be difficult. Imaging can contribute to the clinical presentation not only by identifying abnormal morphology of various supporting soft tissue structures but also by providing referring clinicians with a sense of how functionally incompetent those structures are by utilizing weight-bearing images and with comparison to the contralateral side. Loading the affected joint and visualizing changes in alignment provide clinicians with information regarding the severity of the abnormality and, therefore, how it should be managed.

Anatomy of Ankle Syndesmotic Ligaments: A Systematic Review of Cadaveric Studies

Diagnosis and management of isolated syndesmotic injuries are controversial and highly debated. Hence, the aim of this study is to explore and gain the current understanding pertaining to detailed anatomy of syndesmotic ligaments through a systematic review of published cadaveric studies. A systematic review was conducted online for literature published in English using PubMed and Google Scholar, as per PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, up to April 30, 2019. Predefined eligibility criteria were applied, and the data thus compiled was analyzed. Study quality was assessed based on Quality Appraisal for Cadaveric Studies (QUACS) scale. A total of 12 studies reporting 365 ankles were included in this review. Considerable inconsistency in the naming and description of syndesmotic ligaments was observed, with only 2 studies reporting the vasculature of the ligaments. Hence further investigation of the anatomy of the syndesmotic ligaments is recommended so as to better inform clinical practice, as awareness of anatomy is critical for assessment, healing, and successful surgical management.Levels of Evidence: Level III: Systematic review of anatomical dissections.

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.

Defining the three most responsive and specific CT measurements of ankle syndesmotic malreduction

PURPOSE

The purpose of this study was to compare the reliability and accuracy of existing computed tomography (CT) methods for measuring the distal tibiofibular syndesmosis in uninjured, paired cadaveric specimens and in simulated malreduction models. It was hypothesized that a repeatable set of measurements exists to accurately and quantitatively describe the typical forms of syndesmotic malreduction using contralateral ankle comparison.

METHODS

Twelve cadaveric lower-leg specimen pairs were imaged with CT to generate models for this study. Thirty-five measurements were performed on each native model. Next, four distinct fibular malreductions were produced via digital simulation and all measurements were repeated for each state: (1) 2-mm lateral translation; (2) 2-mm posterior translation; (3) 7-degree external rotation; (4) the previous three states combined. The modified standardized response mean (mSRM) was calculated for each measurement. To assess rater reliability and side-to-side agreements of the native state measurements, intraclass correlation coefficients (ICC) and Pearson correlation coefficients (PCC) were calculated, respectively.

RESULTS

The most responsive measurements for detecting isolated malreduction were the Leporjärvi clear space for lateral translation, the Nault anterior tibiofibular distance for posterior translation, and the Nault talar dome angle for external rotation of the fibula. These measurements demonstrated fair to excellent inter-rater ICCs (0.64-0.76) and variable side-to-side PCCs (0.14-0.47).

CONCLUSIONS

The most reliable method to assess the syndesmosis on CT was to compare side-to-side differences using three distinct measurements, one for each type of fibular malreduction, allowing assessment of the magnitude and directionality of syndesmosis malreduction. Reliable evaluation is essential for assessing subtle syndesmosis injuries, malreduction and surgical planning.