APKASS Consensus Statement on Chronic Syndesmosis Injury,Part 1: Clinical Manifestation,Radiologic Examination,Diagnosis Criteria,Classification,and Nonoperative Treatment

Abstract

Background:

Clinical manifestation, radiologic examination, diagnostic criteria, classification, and nonoperative treatment strategies regarding chronic syndesmosis injury remain unclear.

Purpose:

An international group of experts representing the fields of sports injuries in the foot and ankle area were invited to collaboratively advance toward consensus opinions based on the best available evidence regarding chronic syndesmosis injuries. All were members of the Asia-Pacific Knee, Arthroscopy and Sports Medicine Society (APKASS).

Study Design:

Consensus statement.

Methods:

From November to December 2020, a total of 111 international experts on sports medicine or ankle surgery participated in a 2-stage Delphi process that included an anonymous online survey and an online meeting. A total of 13 items with 38 statements were drafted by 13 core authors. Of these, 4 items with 15 clinical questions and statements were related to the clinical manifestation, radiologic examination, diagnostic criteria, classification, and nonoperative treatment strategies for chronic syndesmosis injury and are presented here. Each statement was individually presented and discussed, followed by a general vote. The strength of consensus was characterized as follows: consensus, 51% to 74%; strong consensus, 75% to 99%; unanimous, 100%.

Results:

Of the 15 questions and statements, 5 reached unanimous support and 10 achieved strong consensus.

Conclusion:

This APKASS consensus statement, developed by international experts in the field, will assist surgeons and physical therapists with diagnosis, classification, and nonoperative treatment strategies for chronic syndesmosis injury.

Keywords

syndesmosis injury ankle clinical manifestation diagnosis consensus

Ankle syndesmosis injury, also called a high ankle sprain, is a frequent athletic trauma accounting for 1% to 18% of all ankle sprains.^21,33 However, a previous radiographic study suggested that about 20.3% of ankle sprains were combined with a syndesmosis injury.²³ This result manifested that because of insufficient recognition, lack of awareness, and misdiagnosis, the incidence of syndesmosis injury may be underestimated. Without prompt and proper treatment, the chronic syndesmosis injury remains symptomatic for >6 months after the initial trauma, with persistent pain, functional disability, and early-stage ankle arthritis.^20,36,38 Despite a large number of radiographic studies having been published focusing on this disorder, the radiographic diagnostic criteria and classification criteria remain under debate. In addition, it is difficult to decide whether a patient with chronic syndesmosis injury should undergo nonoperative management or proceed to surgery, as there is still a lack of conclusive evidence.

Experts from the Asia-Pacific Knee, Arthroscopy and Sports Medicine Society (APKASS) convened to develop evidence-based consensus statements in order to assist surgeons and physiotherapists manage this challenging disorder. The purpose of this article was to report the results of discussions regarding clinical manifestation, radiologic examination, diagnostic criteria, classification, and nonoperative treatment that took place at the 2020 APKASS international consensus meeting on chronic syndesmosis injury.

Methods

A core group of 13 authors drafted and refined 13 items consisting of 38 clinical questions and statements, which were then assigned to at least 1 of the authors to research and summarize the currently available evidence. Our consensus methodology was designed using a 2-stage Delphi process, which included an online survey (November 20, 2020; stage 1) and an online meeting (December 20, 2020; stage 2). The final document we sent out for stage 1 of the consensus process featured 8 items and 29 statements (available as Supplemental Material). Each statement was individually presented and discussed, followed by a general vote.

Stage 1

We invited 21 experts to fill out the online questionnaire (www.surveymonkey.com). For each of the 29 statements, the experts could respond with agree, disagree, or don’t know/not sure, as well as submit optional comments. One author (Y.S.) compiled the survey results and shared them with the core author group for analysis. Statements that achieved consensus (67%, or a two-thirds supermajority) were not discussed further. Consensus was reached on 19 of the 29 initial statements.

Stage 2

Besides the core group of 13 authors, 98 experts in the field attended the online meeting via Zoom. The remaining 5 items (9 statements) underwent voting per stage 1, then all statements that did not achieve consensus after the online survey were displayed and discussed using PowerPoint (Microsoft Corp) by each responsible author, after which 1 of the following 2 steps was taken:

Step 1

If inconsistent opinions were proposed and supported by 2 additional participants during the discussion, modification was required and an amendment motion was made, and the statement was modified if the proportion of votes in favor of doing so was ≥67%.

Step 2

When the participating 111 experts did not propose any further modifications, the group voted for or against the statement. If the proportion of favorable votes was ≤50%, the statement was excluded from the overall consensus statement. If the proportion of favorable votes was >50%, the statement was passed and was included in the overall consensus statement. The strength of consensus was characterized as follows: 51% to 74% indicated consensus; 75% to 99% indicated strong consensus; and 100% indicated unanimous consensus.

A draft of the manuscript was circulated to all 13 core authors, and all comments/edits were incorporated.

Results

Four items with 15 clinical questions are included in this section. Of these 15 questions, 5 reached unanimous support and 10 achieved strong consensus.

Item 1: Clinical Manifestation and Presentation
Statement: Signs and symptoms of chronic syndesmosis injury are nonspecific. A high index of suspicion is warranted for symptomatic post-traumatic ankle pain. Radiological syndesmosis malreduction may be underreported, but its clinical significance is debated.

Vote: Agree 100% (unanimous)

Item 2: Imaging Examination Including Radiography, Computed Tomography, Ultrasonography, and Magnetic Resonance Imaging
Question 1: How to reveal latent instability at the syndesmosis?

Response: Magnetic resonance imaging (MRI) combined with the other imaging modalities could have the possibility of diagnosing instability less invasively compared with arthroscopy.

Vote: Agree 95.2% (strong consensus)

Question 2: What is known about ultrasonography to diagnose syndesmosis injury?

Response: There have been few reports about ultrasonography. It could be a reliable method because dynamic stress examination could be performed to detect a disruption of the anterior inferior tibiofibular ligament (AITFL) by experienced sonographers and doctors. However, it may be less effective for assessing the interosseous membrane and posterior inferior tibiofibular ligament (PITFL).

Vote: Agree 100% (unanimous)

Question 3: Is MRI the most reliable imaging method?

Response: MRI is one of the most reliable methods. Combined with other examinations, MRI is helpful to diagnose chronic syndesmosis instability. However, the detection of the injured ligaments on MRI becomes less reliable with time.

Vote: Agree 95.7% (strong consensus)

Item 3: Diagnosis Criteria, Types, and Classifications for Chronic Syndesmosis Injury
Question 1: How to classify chronic syndesmosis injury through medical history and physical examination?

Response: No definite diagnosis and classification can be made for chronic syndesmosis injury based on medical history and physical examination.

Vote: Agree 90.5% (strong consensus)

Question 2: How to classify chronic syndesmosis injury based on the involved structures?

Response: The grading and the classification of chronic syndesmosis injury can be made based on the involved structures. The structures include the AITFL, interosseous ligament, interosseous membrane, PITFL, and the deltoid ligament.

Vote: Agree 85.7% (strong consensus)

Question 3: What are the criteria to select the radiological examination for chronic syndesmosis injury?

Response: Radiographs should be the first option for evaluating chronic syndesmosis injury. With significantly higher sensitivity, MRI should be done for the suspected syndesmosis injury, which cannot be detected on radiograph or computed tomography (CT).

Vote: Agree 96.4% (strong consensus)

Question 4: How to diagnose and classify chronic syndesmosis injury on radiographs?

Response: Tibiofibular clear space (TFCS) and tibiofibular overlap (TFO) on radiography can be used to aid in the diagnosis of syndesmosis injury, but should not be solely relied on for determining syndesmotic stability and treatment strategies.

Vote: Agree 100% (unanimous)

Question 5: What are the criteria for CT and weightbearing CT?

Response: Published studies have used different measurements of linear distance to identify an increased separation across the syndesmosis or a malalignment between the tibia and fibula.

Vote: Agree 90.5% (strong consensus)

Question 6: What are the criteria for chronic syndesmosis injury on MRI?

Response: The direct criteria include absent ligament, abnormal course, wavy, irregular thickening, and abnormal increased signal on axial MRI and lambda sign on coronal MRI.

Vote: Agree 100% (unanimous)

Question 7: How to define chronic syndesmosis injury?

Response: A syndesmotic injury can be classified as acute, subacute, and chronic based on the time duration of the symptoms.

Vote: Agree 95.2% (strong consensus)

Question 8: How to define the type of chronic syndesmosis injury?

Response: Under the traditional classification standard, chronic syndesmosis injury can be categorized into stable sprain, latent diastasis, and frank diastasis on the basis of radiography. However, with the popularization of MRI and arthroscopy, it is important to build an adapted classification system, which requires further research and clinical validation.

Vote: Agree 95.2% (strong consensus)

Question 9: How to diagnose and classify chronic syndesmosis injury via arthroscopy?

Response: The cutoff for the diagnosis of syndesmosis instability is recommended as 3.0 mm of the length of the opening in the dissector. A grading system should be easily applicable and should help predict the clinical outcomes to play a guiding role in choosing surgical treatment options.

Vote: Agree 76.2% (strong consensus)

Item 4: Indications, Methods, and Outcomes for Nonoperative Treatment
Statement 1: Regarding management of syndesmotic injuries without an ankle fracture, symptomatic syndesmotic sprains without diastasis and evidence of joint instability on imaging should be managed nonoperatively with a non-weightbearing cast.

Vote: Agree 100% (unanimous)

Statement 2: Syndesmotic injuries without a fracture that are treated nonoperatively mostly take longer to heal.

Vote: Agree 75% (strong consensus)

Discussion

Of the 15 questions and statements associated with clinical manifestation, radiologic examination, diagnosis criteria, classification, and nonoperative treatment for chronic syndesmosis injury, 5 questions reached unanimous support and 10 achieved strong consensus.

The clinical presentation of chronic syndesmosis injury is similar to that for chronic ankle instability caused by a lateral ankle ligament injury, which usually involves a history of ankle sprain, persistent pain, swelling, and a giving-way sensation.^2,13,21 However, syndesmosis injury typically has a trauma history mechanism of ankle external rotation, which can provide clues to suspect this differential diagnosis.^13,21 To date, several special tests on physical examination help to diagnose syndesmosis injury: squeeze test; palpation test; fibular translation test; Cotton test; external rotation test; and dorsiflexion compression test. A study by de César et al⁵ compared MRI with clinical tests including external rotation test and squeeze test and found the sensitivity and specificity were 30% and 93.5% for the squeeze test, and 20% and 84.8% for the external rotation test, respectively. Sman et al³⁰ reviewed 8 clinical diagnostic tests and found that only the squeeze test had clinically important results while other clinical tests showed low diagnostic accuracy and reliability. Therefore, the signs and symptoms of chronic syndesmosis injury are nonspecific. Additional diagnostic tests, such as MRI and arthroscopy, should be considered before making a final diagnosis and formulating a treatment strategy for chronic syndesmosis injury.

Radiologic examination including radiographs, CT, ultrasonography, and MRI are widely used in the diagnosis and classification of a chronic syndesmosis injury. Chun et al³ systematically reviewed and concluded that compared with MRI, CT and radiography had significantly poor sensitivity and similar specificity in diagnosing syndesmosis injury, which helps to distinguish ankle fracture, but there are concerns about radiation exposure. Therefore, MRI should be considered in diagnosing syndesmosis injury as a standard method for comparing arthroscopic findings for syndesmosis injury. The signs of syndesmotic ligament injury and tearing can be seen directly on the MRI scan. The positive findings consist of previously reported criteria: (1) no visualization of syndesmotic ligament; (2) abnormal course, wavy, irregular thickening of the distal tibiofibular ligament; (3) increased signal of the distal tibiofibular ligament on T2- and T1-weighted images; and (4) high-intensity signal seen on coronal MRI inside the tibiofibular space (lambda sign).^9,17,24,35 According to Han et al,⁹ the sensitivity, specificity, and accuracy of MRI were 90.0%, 94.8%, and 93.4%, respectively. Axial MRI is known to be the most useful and recommended tool in the noninvasive diagnosis of a syndesmosis injury. However, Randell et al²² found that MRI was positive for detecting a syndesmosis injury in chronic injuries after 12 weeks in 83.3% of patients, compared with 100% if done within 6 weeks, which demonstrated that the detection of the injured syndesmotic ligaments on MRI may become less reliable with time.

Compared with MRI, radiographs are less costly and more time saving; they can show indirect signs of a syndesmotic ligament injury on anteroposterior (AP) view and mortise view. Among several parameters, the TFCS and the TFO are emphasized by previous studies.^{10,19,24,27,28,39} Harper and Keller¹⁰ proposed the following criteria to be consistent with a normal tibiofibular relationship: (1) a TFCS <6 mm on AP and mortise radiographs; (2) TFO at the incisura fibularis tibiae ≥6 mm or ≥42% of the fibular width; and (3) TFO >1 mm on the mortise view. However, Ryan and Rodriguez²⁵ found the average of TFCS was 5.6 mm in syndesmosis injury patients, which manifested that reducible syndesmotic instability may not be detectable on radiography according to the criteria of Harper and Keller. Shah et al²⁸ also proposed that lack of TFO on the mortise view can also represent a normal variant, and the radiographic criteria may lead to unnecessary operative intervention. This evidence suggests that radiographs can only aid in the diagnosis of syndesmosis injury rather than determine the treatment strategy.

As for CT and weightbearing CT, linear and area measurement on the axial plane assists with the diagnosis of a syndesmosis injury. Ahn et al¹ measured syndesmosis widening on CT and concluded that widening >2 mm had a high likelihood of a syndesmosis lesion. Hagemeijer et al⁸ considered the syndesmotic area as one of the most applicable parameters for detecting syndesmosis instability in the axial plane. In addition, Malhotra et al¹⁴ measured the angle subtended by 2 lines drawn tangent to the anterior and posterior surfaces of the distal tibia and lateral malleolus 1 cm above the talar dome, which decreased in patients with diastasis of the syndesmosis.

Ultrasonography may allow visualization of the AITFL but Milz et al¹⁶ found ultrasound only correctly diagnosed 66% of patients with MRI-diagnosed AITFL injury. Mei-Dan et al¹⁵ found the specificity and sensitivity of dynamic ultrasound was 89%. However, ultrasonography is highly dependent on the sonographers’ and doctors’ skill, and there were still a limited number of reports regarding ultrasonography.

Previous researchers have emphasized the importance of arthroscopy in the diagnosis and differentiation of syndesmosis instability.^31,37 Under arthroscopy, torn parts of the syndesmotic ligament can be directly seen. On the other hand, to evaluate the degree of instability, an arthroscopic probe can be inserted between the tibia and fibula and rotated to measure the widening and movement between the individual joint sections. Normally, the ankle mortise widens about 1 mm as the intact ankle joint moves from full plantarflexion to full dorsiflexion²⁶; however, injury of the syndesmosis results in widening of the syndesmosis. Colcuc et al⁴ semiquantitatively assessed the grade of dislocation through the length of the opening: grade 1 (1.0-1.5 mm), grade 2 (1.5-2.5 mm), and grade 3 (2.5-3.5 mm). Compared with grades 1 and 2, grade 3 showed worse clinical outcomes after reconstructive surgery at follow-up. According to the arthroscopic syndesmotic assessment (ASA) tool by Lubberts et al,¹¹ an ASA value ≥3.1 mm is defined as an unstable syndesmosis. Turky et al³² established a grading system as follows: grade 0, ≤2 mm (normal); grade 1, ≤2 to 4 mm; and grade 2, ≥5 mm; and the results were labelled as “xAxP” (A, anterior; P, posterior). The diagnosis criteria and grading of arthroscopic assessment of syndesmosis injury are areas still under discussion.

In general, patients without diastasis or joint dynamic instability can be treated nonoperatively. Lubberts et al¹² systematically reviewed the previous study and suggested stable grade 2 syndesmosis injury could be treated nonoperatively. Nussbaum et al¹⁸ treated 60 patients with stable syndesmosis injury nonoperatively and achieved an overall good result. It was emphasized that the rehabilitation protocol, including rigid immobilization, as well as functional and proprioceptive exercises, played an important role in the recovery of sporting function. However, it should also be mentioned that although nonoperative treatment could achieve satisfactory outcomes in patients without diastasis, an overly conservative treatment strategy may result in sprain recurrence, persistent ankle pain, and formation of heterotopic ossification. Compared with lateral ankle ligament injury, syndesmotic ligament injury generally takes longer to heal. Wright et al³⁸ analyzed the ankle sprain injury in National Hockey League players and found syndesmosis sprains represented a significant injury in hockey players with an extended time lost.

The classification system of chronic syndesmosis injury plays important roles in the treatment strategy. Classically, Edward and DeLee⁶ divided syndesmotic sprains into stable ankle sprain and unstable ankle sprain on the basis of radiography, with the latter further divided into latent diastasis and frank diastasis. According to this classification system, stable ankle sprains were recommended to undergo conservative treatment, However, this system was based on the observation of just 6 cases, and MRI and arthroscopy were not applied in this system, which limited the accuracy of the injury assessment.³⁴ Gerber et al⁷ proposed the West Point Ankle Grading System based on clinical examinations. Sikka et al²⁹ classified syndesmotic ankle sprains into 4 grades on the basis of MRI examination. However, current classifications remain insufficient for differentiating between injury and instability to guide treatment strategy, and thus this represents an area in need of further scientific investigation.³⁶

Conclusion

The 4 items with 15 clinical questions and statements of this APKASS consensus statement, developed by experts in the field, focused on the clinical manifestation, radiologic examination, diagnosis criteria, classification, and nonoperative treatment of chronic syndesmosis injury and will assist surgeons and physical therapists in the management of this challenging disorder.

Supplemental Material

Supplemental Material, sj-pdf-1-ojs-10.1177_23259671211021057 - APKASS Consensus Statement on Chronic Syndesmosis Injury, Part 1: Clinical Manifestation, Radiologic Examination, Diagnosis Criteria, Classification, and Nonoperative Treatment

Supplemental Material, sj-pdf-1-ojs-10.1177_23259671211021057 for APKASS Consensus Statement on Chronic Syndesmosis Injury, Part 1: Clinical Manifestation, Radiologic Examination, Diagnosis Criteria, Classification, and Nonoperative Treatment by Chen Jiao, Jianchao Gui, Hiroaki Kurokawa, Yasuhito Tanaka, Patrick Yung, Seung Hwan Han, Chayanin Angthong, Yujie Song, Yinghui Hua, Hongyun Li, Zhongmin Shi, Qi Li, Samuel K.K. Ling and on behalf of the APKASS Foot and Ankle Committee in Orthopaedic Journal of Sports Medicine

Footnotes

Final revision submitted April 1, 2021; accepted April 20, 2021.

Supplemental Material for this article is available at

This article was published in Orthopaedic Journal of Sports Medicine (Volume 9 Issue 6, June 2021) and will appear in a future issue of AP-SMART. Minor differences may exist between this version and the other to be consistent with editorial style.

Acknowledgment

The authors acknowledge the following for their participation: Jun Chen, MD (Dongyang People’s Hospital, Wenzhou Medical University, China); Bo Feng, MD (The Third Clinical Medical College of Inner Mongolia Medical University, China); Fulong Gu, MD (Nantong Traditional Chinese Medicine Hospital, China); Xueping Gu, MD (The Affiliated Suzhou Hospital of Nanjing Medical University, China); Qinglin Han, MD (The Affiliated Hospital of Nantong University, China); Yuefeng Hao, MD (The Affiliated Suzhou Hospital of Nanjing Medical University, China); Jiang Heng, MD (Tianxiang East Hospital, China); Dong Jiang, MD, PhD (Peking University Third Hospital, China); Dongliang Shi, MD (Yangzhi Rehabilitation Hospital, Tongji University School of Medicine, China); Jin Su Kim, MD (Sejong Sports Medicine and Sports Performance Center, Republic of Korea); Hak Jun Kim, MD (Korea University College of Medicine, Republic of Korea); Jiaping Lan, MD (Suining Central Hospital, China); Lei Li, MD (Suining Central Hospital, China); Fei Li, MD (The 1st Hospital of Tsinghua University, China); Ding Li, MD (The 2nd Xiangya Hospital, Center South University, China); Yi Liu, MD (Guangdong Provincial Hospital of Traditional Chinese Medicine, China); Wei Luo, MD (Longkou Traditional Chinese Medicine Hospital, China); Kwang Hwan Park, MD (Yonsei University, Republic of Korea); Jae Yong Park, MD (Hallym University Sacred Heart Hospital, Republic of Korea); Yan Qi, MD (Yangzhi Rehabilitation Hospital, Tongji University School of Medicine, China); Yuanyuan Qian, MD (The First People’s Hospital of Changshu City, China); Zilong Sheng, MD (Beijing Huairou Hospital, China); Bin Song, MD (Sun Yat-Sen Memorial Hospital, China); Tong Su, MD (Peking University Third Hospital, China); Xu Tao, MD (Luzhou Traditional Chinese Medicine Hospital, China); Nattachai Thaengthong, MD (Sakaeo Crown Prince Hospital, Thailand); Yiran Wang, MD (Huashan Hospital, Fudan University, China); Shaoshan Wang, MD (Shandong Provincial Hospital of Traditional Chinese Medicine, China); Bin Wu, MD (Shanghai Jiangong Hospital, China); Hansong Xia, MD (The 3rd Xiangya Hospital, Central South University, China); Qian Xu, MD (910th Hospital of PLA, China); Guoyong Yang, MD (No. 1 Orthopedics Hospital of Chengdu, China); Zhengshuang Yue, MD (Xiaoshan TCM Hospital, China); Kexiang Zhang, MD (The 3rd Xiangya Hospital, Central South University, China); Xiaoming Zhao, MD (The People’s Hospital of Lishui District, China); Yuan Zhu, MD (Shanghai Ruijin Hospital Foot and Ankle Center, Shanghai Jiaotong University, China); Chuan He, MD (The First Affiliated Hospital of Kunming Medical University, China); Qianru Li, MD (Huashan Hospital, Fudan University, China); Junyoung Lee, MD (Chosun University Hospital, Republic of Korea); Kyoung Min Lee, MD (Seoul National University Bundang Hospital, Republic of Korea); Min Luo, MD (Dongyang Traditional Chinese Medicine Hospital, China); Haidong Ma, MD (Tangshan Second Hospital, China); Shuiwah Man, MBChB (Queen Elizabeth Hospital, Hong Kong, China); Young Koo Lee, MD (Soonchunhyang University Bucheon Hospital, Republic of Korea); Yanming Liu, MD (Luzhou Traditional Chinese Medicine Hospital, China); Eva Au, MSc (Queen Elizabeth Hospital, Hong Kong, China); Angela Ho, MBChB (Caritas Medical Centre, Hong Kong China); Cong Wang, MD (Shuguang Hospital, China); Jaeho Cho, MD (Chuncheon Sacred Heart Hospital, Republic of Korea); Jungwoo Choi, MD (Korea University Guro Hospital, Republic of Korea); Satetha Vasaruchapong, MD (Chakri Naruebodindra Medical Institute, Thailand); Chan Kang, MD (Chungnam National University Hospital, Republic of Korea); Qiang Hua, MD (Affiliated Sports Hospital of Chengdu Sport University, China); Hyun Woo Park, MD (Dankook University Hospital, Republic of Korea); Kwai Ming Siu, MBChB (The Hong Kong Orthopaedic Association, Hong Kong, China); Yeonjoo Jeong, MD (Chosun University Hospital, Republic of Korea); Changuoung Jung, MD (Leechuntaek Hospital, Republic of Korea); Jiao Sha, MD (The First People’s Hospital of Taicang, China); Feng Tian, MD (Xi’an Honghui Hospital, China); Yunfeng Shen, MD (Huashan Hospital, Fudan University, China); Pisut Tuntanatipchai, MD (Sakaeo Crown Prince Hospital, Thailand); Guixin Wang, MD (Tianjin Hospital, China); Hui Zhao, MD (Beijing Chaoyang Hospital, China); Meng Shi, MD (Shuguang Hospital, China); Zhiwei Zhang, MD (Yueyang Second People’s Hospital, China); Songwut Thitiboonsuwan, MD (Navamindradhiraj University, Thailand); Min Zhu, MD (920th Hospital of PLA, China); Suwimol Prusmetikul, MD (Ramathibodi Hospital, Mahidol University, Thailand).

References

Ahn

Choi

Kim

Lee

. Isolated syndesmosis diastasis: computed tomography scan assessment with arthroscopic correlation. Arthroscopy. 2017;33(4):828–834.

Boytim

Fischer

Neumann

. Syndesmotic ankle sprains. Am J Sports Med. 1991;19(3):294–298.

Chun

Cho

Min

, et al. Diagnostic accuracy of radiologic methods for ankle syndesmosis injury: a systematic review and meta-analysis. J Clin Med. 2019;8(7):968.

Colcuc

Fischer

Colcuc

, et al. Treatment strategies for partial chronic instability of the distal syndesmosis: an arthroscopic grading scale and operative staging concept. Arch Orthop Trauma Surg. 2016;136(2):157–163.

de César

Avila

de Abreu

. Comparison of magnetic resonance imaging to physical examination for syndesmotic injury after lateral ankle sprain. Foot Ankle Int. 2011;32(12):1110–1114.

Edwards

Jr DeLee

. Ankle diastasis without fracture. Foot Ankle. 1984;4(6):305–312.

Gerber

Williams

Scoville

Arciero

Taylor

. Persistent disability associated with ankle sprains: a prospective examination of an athletic population. Foot Ankle Int. 1998;19(10):653–660.

Hagemeijer

Chang

Abdelaziz

, et al. Range of normal and abnormal syndesmotic measurements using weightbearing CT. Foot Ankle Int. 2019;40(12):1430–1437.

Han

Lee

Kim

Suh

Choi

. Chronic tibiofibular syndesmosis injury: the diagnostic efficiency of magnetic resonance imaging and comparative analysis of operative treatment. Foot Ankle Int. 2007;28(3):336–342.

10.

Harper

Keller

. A radiographic evaluation of the tibiofibular syndesmosis. Foot Ankle Int. 1989;10(3):156–160.

11.

Lubberts

Guss

Vopat

, et al. The arthroscopic syndesmotic assessment tool can differentiate between stable and unstable ankle syndesmoses. Knee Surg Sports Traumatol Arthrosc. 2020;28(1):193–201.

12.

Lubberts

van Dijk

PAD

Donovan

van Dijk

Calder

. Stable and unstable grade II syndesmotic injuries require different treatment strategies and vary in functional outcomes: a systematic review. J ISAKOS. 2016;1(4):192–197.

13.

Magan

Golano

Maffulli

Khanduja

. Evaluation and management of injuries of the tibiofibular syndesmosis. Br Med Bull. 2014;111(1):101–115.

14.

Malhotra

Cameron

Toolan

. Diagnosing chronic diastasis of the syndesmosis: a novel measurement using computed tomography. Foot Ankle Int. 2014;35(5):483–488.

15.

Mei-Dan

Kots

Barchilon

, et al. A dynamic ultrasound examination for the diagnosis of ankle syndesmotic injury in professional athletes: a preliminary study. Am J Sports Med. 2009;37(5):1009–1016.

16.

Milz

Steinborn

, et al. Lateral ankle ligaments and tibiofibular syndesmosis. 13-MHz high-frequency sonography and MRI compared in 20 patients. Acta Orthop Scand. 1998;69(1):51–55.

17.

Muhle

Frank

Rand

, et al. Tibiofibular syndesmosis: high-resolution MRI using a local gradient coil. J Comput Assist Tomogr. 1998;22(6):938–944.

18.

Nussbaum

Hosea

Sieler

Incremona

Kessler

. Prospective evaluation of syndesmotic ankle sprains without diastasis. Am J Sports Med. 2001;29(1):31–35.

19.

Ostrum

De Meo

Subramanian

. A critical analysis of the anterior-posterior radiographic anatomy of the ankle syndesmosis. Foot Ankle Int. 1995;16(3):128–131.

20.

Pereira

Koval

Resnick

, et al. Tibiotalar contact area and pressure distribution: the effect of mortise widening and syndesmosis fixation. Foot Ankle Int. 1996;17(5):269–274.

21.

Rammelt

Obruba

. An update on the evaluation and treatment of syndesmotic injuries. Eur J Trauma Emerg Surg. 2015;41(6):601–614.

22.

Randell

Marsland

Ballard

Forster

Lutz

. MRI for high ankle sprains with an unstable syndesmosis: posterior malleolus bone oedema is common and time to scan matters. Knee Surg Sports Traumatol Arthrosc. 2019;27(9):2890–2897.

23.

Roemer

Jomaah

Niu

, et al. Ligamentous injuries and the risk of associated tissue damage in acute ankle sprains in athletes: a cross-sectional MRI study. Am J Sports Med. 2014;42(7):1549–1557.

24.

Ryan

Hills

Chang

Wilson

. The lambda sign: a new radiographic indicator of latent syndesmosis instability. Foot Ankle Int. 2014;35(9):903–908.

25.

Ryan

Rodriguez

. Outcomes and return to activity after operative repair of chronic latent syndesmotic instability. Foot Ankle Int. 2016;37(2):192–197.

26.

Sarsam

Hughes

. The role of the anterior tibio-fibular ligament in talar rotation: an anatomical study. Injury. 1988;19(2):62–64.

27.

Scheyerer

Helfet

Wirth

Werner

. Diagnostics in suspicion of ankle syndesmotic injury. Am J Orthop (Belle Mead NJ). 2011;40(4):192–197.

28.

Shah

Kadakia

Tan

, et al. Radiographic evaluation of the normal distal tibiofibular syndesmosis. Foot Ankle Int. 2012;33(10):870–876.

29.

Sikka

Fetzer

Sugarman

, et al. Correlating MRI findings with disability in syndesmotic sprains of NFL players. Foot Ankle Int. 2012;33(5):371–378.

30.

Sman

Hiller

Refshauge

. Diagnostic accuracy of clinical tests for diagnosis of ankle syndesmosis injury: a systematic review. Br J Sports Med. 2013;47(10):620–628.

31.

Takao

Ochi

Oae

Naito

Uchio

. Diagnosis of a tear of the tibiofibular syndesmosis: the role of arthroscopy of the ankle. J Bone Joint Surg Br. 2003;85(3):324–329.

32.

Turky

Menon

Saeed

. Arthroscopic grading of injuries of the inferior tibiofibular syndesmosis. J Foot Ankle Surg. 2018;57(6):1125–1129.

33.

Valkering

Vergroesen

Nolte

. Isolated syndesmosis ankle injury. Orthopedics. 2012;35(12):e1705–e1710.

34.

van Dijk

Longo

Loppini

, et al. Classification and diagnosis of acute isolated syndesmotic injuries: ESSKA-AFAS consensus and guidelines. Knee Surg Sports Traumatol Arthrosc. 2016;24(4):1200–1216.

35.

Vogl

Hochmuth

Diebold

, et al. Magnetic resonance imaging in the diagnosis of acute injured distal tibiofibular syndesmosis. Invest Radiol. 1997;32(7):401–409.

36.

Vopat

Lubberts

DiGiovanni

. Current trends in the diagnosis and management of syndesmotic injury. Curr Rev Musculoskelet Med. 2017;10(1):94–103.

37.

Wagener

Beumer

Swierstra

. Chronic instability of the anterior tibiofibular syndesmosis of the ankle: arthroscopic findings and results of anatomical reconstruction. BMC Musculoskelet Disord. 2011;12:212.

38.

Wright

Barile

Surprenant

Matava

. Ankle syndesmosis sprains in National Hockey League players. Am J Sports Med. 2004;32(8):1941–1945.

39.

Yaradılmış

Polat

Uslu

, et al. The evaluation of radiological measurements used in diagnosis and treatment of syndesmosis injury: a regional study in Turkey. Jt Dis Relat Surg. 2020;31(1):123–129.

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