Abstract:Forced external rotation is hypothesized as the key mechanism of syndesmotic ankle injuries, inducing a three‐dimensional deviation from the normal distal tibiofibular joint (DTFJ) alignment. However, current diagnostic imaging modalities are impeded by a two‐dimensional assessment, without considering ligamentous stabilizers. Therefore, our aim is threefold: (1) to construct an articulated statistical shape model of the normal DTFJ with the inclusion of ligamentous morphometry, (2) to investigate the effect o… Show more
“…5 ). This was consistent with the description of Lauge-Hansen typing in the clinic 14 – 16 . Figure 5 Stress distribution during a stage I supination-external rotation ankle injury.…”
By establishing a three-dimensional finite element model of ankle injury arising from supination and external rotation, the stress characteristics of the posterior malleolar surface can be obtained, and analysis of the corresponding stress on the lateral ankle can be conducted. Thin-layer computed tomography images of normal ankle joint in the supination and external rotation nonweight-bearing states was selected, to construct a three-dimensional data model of each ankle joint. A load was applied to examine different ankle joint stress values and pressure distributions on the surface of the posterior ankle joint. A 600 N vertical compressive and 10 Nm internal rotation load was applied in Stage III (removing the anterior tibiofibular ligament and the posterior tibiofibular ligament) of SER (supination-external rotation). When the lateral malleolar was intact, the maximum stress (132.7 MPa) was located at the point of attachment of the posterior tibiofibular ligament to the fibula, and the maximum pressure of the posterior malleolar surface was lower than 4.505 MPa. When a lateral malleolar fracture was present, the maximum stress (82.72 MPa) was located on the fibular fracture surface, and the maximum pressure of the posterior malleolar surface was 8.022 MPa. This study shows that reconstruction of the lateral malleolus in supination-external rotation ankle injuries significantly affects the stress distribution at the posterior malleolar joint surface. Through this reconstruction, the pressure distribution of the posterior malleolar joint surface can be significantly reduced.
“…5 ). This was consistent with the description of Lauge-Hansen typing in the clinic 14 – 16 . Figure 5 Stress distribution during a stage I supination-external rotation ankle injury.…”
By establishing a three-dimensional finite element model of ankle injury arising from supination and external rotation, the stress characteristics of the posterior malleolar surface can be obtained, and analysis of the corresponding stress on the lateral ankle can be conducted. Thin-layer computed tomography images of normal ankle joint in the supination and external rotation nonweight-bearing states was selected, to construct a three-dimensional data model of each ankle joint. A load was applied to examine different ankle joint stress values and pressure distributions on the surface of the posterior ankle joint. A 600 N vertical compressive and 10 Nm internal rotation load was applied in Stage III (removing the anterior tibiofibular ligament and the posterior tibiofibular ligament) of SER (supination-external rotation). When the lateral malleolar was intact, the maximum stress (132.7 MPa) was located at the point of attachment of the posterior tibiofibular ligament to the fibula, and the maximum pressure of the posterior malleolar surface was lower than 4.505 MPa. When a lateral malleolar fracture was present, the maximum stress (82.72 MPa) was located on the fibular fracture surface, and the maximum pressure of the posterior malleolar surface was 8.022 MPa. This study shows that reconstruction of the lateral malleolus in supination-external rotation ankle injuries significantly affects the stress distribution at the posterior malleolar joint surface. Through this reconstruction, the pressure distribution of the posterior malleolar joint surface can be significantly reduced.
“…Future studies are required to determine cut‐off values that may indicate the amount of displacement that might lead to chronic instability and require a certain type of treatment strategy. Bringing these reported displacements in relation to patient‐reported outcomes, shape morphometrics, MRI findings over a long‐term follow‐up, will ultimately aid in determining those patients that require a conservative or surgical treatment for their syndesmotic ankle injury [17, 27].…”
Purpose Acute syndesmotic ankle injuries continue to impose a diagnostic dilemma and it remains unclear whether weightbearing and/or external rotation should be added during the imaging process. Therefore, the aim of this study was to assess if combined weightbearing and external rotation increases the diagnostic sensitivity of syndesmotic ankle instability using weightbearing CT (WBCT) imaging, compared to isolated weightbearing. Methods In this retrospective study, patients with an acute syndesmotic ankle injury were analysed using a WBCT (N = 21; Age = 31.6 ± 14.1 years old). Inclusion criteria were an MRI conirmed syndesmotic ligament injury imaged by a WBCT of the ankle during weightbearing and combined weightbearing-external rotation. Exclusion criteria consisted of fracture associated syndesmotic injuries. Three-dimensional (3D) models were generated from the CT slices. Tibioibular displacement and talar rotation were quantiied using automated 3D measurements (anterior tibioibular distance (ATFD), Alpha angle, posterior Tibioibular distance (PTFD) and Talar rotation (TR) angle in comparison to the contralateral non-injured ankle.
ResultsThe diference in neutral-stressed Alpha angle and ATFD showed a signiicant diference between patients with a syndesmotic ankle lesion and contralateral control (P = 0.046 and P = 0.039, respectively). The diference in neutral-stressed PTFD and TR angle did not show a signiicant diference between patients with a syndesmotic ankle lesion and healthy ankles (n.s.). Conclusion Application of combined weightbearing-external rotation reveals an increased ATFD in patients with syndesmotic ligament injuries. This study provides the irst insights based on 3D measurements to support the potential relevance of applying external rotation during WBCT imaging. In clinical practice, this could enhance the current diagnostic accuracy of subtle syndesmotic instability in a non-invasive manner. However, to what extent certain displacement patterns require operative treatment strategies has yet to be determined in future studies. Level of evidence Level III.
“…So syndesmotic sprain or high ankle sprain is a type of distal tibiofibular syndesmosis injury that may have a rupture of the distal tibiofibular ligaments and interosseous membrane. 2,[5][6][7] The occurrence of HAS is not only affected by the external stability of the distal tibiofibular joint (DTFJ) provided by the ligament complex (anterior distal tibiofibular ligament, posterior distal tibiofibular ligament, transverse ligament, and interosseous ligament), but also by the endogenous stability of the fibular notch (FN). 8 The distal tibiofibular syndesmosis consists of the distal tibia, the distal fibula and the distal tibiofibular syndesmosis ligament complex.…”
Section: Introductionmentioning
confidence: 99%
“…The high ankle ligaments (also called the syndesmosis) are located around the distal of tibia and fibula, opposite the more vulnerable ligaments on the outside of the ankle. So syndesmotic sprain or high ankle sprain is a type of distal tibiofibular syndesmosis injury that may have a rupture of the distal tibiofibular ligaments and interosseous membrane 2,5–7 . The occurrence of HAS is not only affected by the external stability of the distal tibiofibular joint (DTFJ) provided by the ligament complex (anterior distal tibiofibular ligament, posterior distal tibiofibular ligament, transverse ligament, and interosseous ligament), but also by the endogenous stability of the fibular notch (FN) 8 …”
ObjectivesThe 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.MethodsOne 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.ResultsIn 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).ConclusionsIn 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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
