Ankle fractures are among of the most frequently addressed injuries by orthopedic surgeons. Ankle fractures have an incidence rate about 107-145 per 100000 in adult population. Approximately 10% of these fractures are concomitant with syndesmotic injury. This percentage is doubled in patients who need open reduction and internal fixation( ORIF).As a result ,it is essential for orthopedic surgeons to accurately diagnose these injuries,which ocurr in up to 40% of weber type B pott's fracture and up to 80% in pott's c. Failure to properly diagnose or treat these injuries can lead to persistent ankle pain ,functional instability and early osteoarthritis. The ankle joint is a synovial joint that connects leg bones :the fibula which ends distally with lateral malleolus and the tibia which ends distally with tibial plafond , medial malleolus and posterior malleolus ,with the talus.It is a complex hinge joint.) 2.Kennedy JG, Soffe KE, Dalla Vedova P, Stephens MM, O'Brien T, Walsh MG, McManus F( Ankle syndesmosis injuries are common, but diagnosing and treating them can be challenging, often leading to differing opinions among healthcare providers. It is crucial for orthopedic surgeons to recognize the complex nature of these injuries, especially when they involve damage to the interosseous membrane. Patients may seek medical attention years after the initial injury, reporting gradual, worsening pain and swelling following physical activity. These symptoms can significantly affect their quality of life.
Diagnostic dilemma of syndesmotic injury in ankle fracture:
The are different modalities regarding the diagnosis:
- X-ray imaging is one of the most commonly used methods for diagnosing ankle syndesmosis injuries. In a normal anteroposterior radiograph, the tibiofibular overlap should be greater than 6 mm, while in a mortise radiograph, it should exceed 1 mm when measured 1 cm above the tibial plafond. Similarly, the tibiofibular clear space should be less than 6 mm in both anteroposterior and mortise views at the same level. Additionally, the medial clear space should be equal to or less than the distance between the talar dome and the tibial plafond. A reduction in tibiofibular overlap, an increase in tibiofibular clear space, or an increase in medial clear space whether observed on weight-bearing or non weight-bearing radiographs suggests syndesmotic disruption.) 6. Pogliacomi F, De Filippo M, Casalini D, Longhi A, Tacci F, Perotta R, Pagnini F, Tocco S, Ceccarelli( While standard radiographic views are useful for evaluating moderate-to-severe ankle syndesmosis injuries, detecting subtle syndesmotic widening remains challenging.
- Computed tomography (CT) provides a clear and direct visualization of the positional alignment of the distal tibiofibular syndesmosis. It allows precise measurement of the syndesmotic gap and facilitates comparison with the contralateral side. As a result, CT is particularly valuable for diagnosing ankle syndesmosis injuries when radiographic findings are inconclusive. A syndesmosis injury is generally indicated if the gap exceeds 6 mm or is more than 2 mm wider than the opposite side.Exposure to CT radiation can cause many hazards to patients.) 3.Elgafy H, Semaan HB, Blessinger B, Wassef A, Ebraheim NA(.
- MRI is the preferred method for diagnosing syndesmosis injuries due to its high sensitivity and specificity. However, examination techniques particularly slice orientation and ankle positioning require standardization to ensure optimal visualization of the distal tibiofibular ligament. The oblique orientation of ligament fibers may result in false positives when compared to intraoperative findings. Additional associated injuries, such as anterior talofibular ligament tears, bone edema, osteochondral lesions, or distal tibiofibular joint incongruities, may also be present. These findings can include ligament discontinuity or irregular, curved, or indistinct ligament contours.The high cost and non availability of MRI hinder and limit it's use in clinical practice.) 8.Kellett JJ, Lovell GA, Eriksen DA, Sampson MJ. Diagnostic imaging of ankle syndesmosis injuries:(
- Ultrasound offers a cost-effective and readily available option that could serve as a screening tool for syndesmotic ligamentous injuries in the ankle. The ultrasound evaluation begins by examining the anterior compartment to check for joint fluid, synovitis, and osteophytes on the tibia or talus. Tendons in the extensor, medial, and lateral compartments are evaluated in both longitudinal and transverse planes. The lateral compartment assessment focuses on the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL). In the medial compartment, the deltoid ligament is assessed in the oblique coronal plane. The syndesmosis is imaged in all cases using the transverse plane through an anterior approach. The anterior-inferior tibiofibular ligament (AITFL) is inspected for continuity and contour, and the tibia-fibula distance (clear space) is measured.) 1.Hagemeijer NC, Lubberts B, Saengsin J, Bhimani R, Sato G, Waryasz GR, Kerkhoffs GMMJ, DiGiovanni CW, Guss D(