Which test is the best? An updated literature review of imaging modalities for acute ankle diastasis injuries

Subtle Syndesmotic Instability

Latent or subtle syndesmotic instability is defined as an injury to the syndesmosis which is not apparent on static radiographs of the ankle. Syndesmotic injuries have also been referred to as high ankle sprains. Injury to the syndesmosis typically occurs with collision sports and often involves an external rotation force to the ankle. Diagnosis can be delayed because of negative initial imaging studies. Physical examination tests including the external rotation test, proximal squeeze test, and fibular shuck test can assist in the diagnosis. Advanced imaging modalities such as MRI and weight-bearing CT have been studied and can provide prognostic indications for management, although arthroscopic stress evaluation remains the benchmark for diagnosis. Both surgical and nonsurgical management techniques have been described, which can assist patients in returning to their preinjury level of function.

Standardized analysis of syndesmosis stability in ankle trauma with an innovative syndesmosis-test-tool: a biomechanical study

When treating ankle fractures, the question of syndesmosis complex involvement often arises. So far, there is no standardized method to reliably detect syndesmosis injuries in the surgical treatment of ankle fractures. For this reason, an intraoperative syndesmosis-test-tool (STT) was developed and compared to the recommended and established hook-test (HT). Tests were performed on cadaveric lower legs (n = 20) and the diastasis was visualized by 3D camera. Tests were performed at 50, 80, and 100 N in native conditions and four instability levels. Instability was induced from anterior to posterior and the reverse on the opposite side. The impact on diastasis regarding the direction, the force level, the instability level, and the device used was checked using a general linear model for repeated measurement. The direction of the induced instability showed no influence on the diastasis during the stability tests. The diastasis measured with the STT increased from 0.5 to 3.0 mm depending on the instability, while the range was lower with the HT (1.1 to 2.3 mm). The results showed that the differentiation between the instability levels was statistically significantly better for the developed STT. The last level of maximum instability was significantly better differentiable with the STT compared to the HT. An average visualizable diastasis of more than 2 mm could only be achieved at maximum instability. In conclusion, the newly developed STT was superior to the commonly used HT to detect instability.

Maisonneuve fracture treated with suture-button system stabilization combined with plate and arthroscopic assistance (SBPAA): Clinical and radiological evaluation in short-medium period

The aim of this study was to estimate the time needed for patients with Maisonneuve fractures to return to routine activities, after treatment with a suture-button system stabilization combined with plate and arthroscopic assistance (SBPAA).

Methods

The study included 13 patients treated at our surgical department from January 2018 to June2022. Specific radiographical follow-up and periodic checks were performed in a short -to-medium term period, to evaluate syndesmosis evolution and tibiofibular overlap with medial clear space (MCS).

Results

Progressive recovery and improvement were observed during follow-up from both radiographic and clinical perspective. Data showed that patients were able to return to full weight-bearing walking around the ninth week and to sport activities in 7.5 months. Long-term complications associated with residual joint stiffness, complex regional pain syndrome, or wound complications were observed in three patients.

Conclusions

Intraoperative arthroscopy represent a valid diagnostic tool to better recognize and evaluate osteochondral lesions in case of syndesmosys. The study demonstrates the importance of intraoperative arthroscopy for recognizing and treating associated osteochondral lesions with proper syndesmosis evaluation. Plate associated to double TightRope represent valid solution to functionally fix and reduce fractures. Additionally, it imitates the normal syndesmosis's anatomy and provides elasticity and robustness, guaranteeing a rapid return to sporting activity. Data and casuistry support these findings.