Acta chirurgiae orthopaedicae
et traumatologiae Čechoslovaca

Acta Chir Orthop Traumatol Cech. 2022; 89(1):37-42 | DOI: 10.55095/achot2022/004

Risk Factors for the Development of Distal Tibiofibular Synostosis after Unstable Ankle FracturesOriginal papers

J. MARVAN^1,*, J. JEŽEK¹, J. VRÁNOVÁ², D. MARVAN³, F. ČÍŽEK³, V. DŽUPA¹

¹ Ortopedicko-traumatologická klinika, 3. lékařská fakulta Univerzity Karlovy a Fakultní nemocnice Královské Vinohrady, Praha

² Ústav lékařské biofyziky a lékařské informatiky, 3. lékařská fakulta Univerzity Karlovy, Praha

³ 3. lékařská fakulta Univerzity Karlovy, Praha

PURPOSE OF THE STUDY:
The study analyses a cohort of patients with surgically treated ankle fractures who developed complete distal tibiofibular synostoses. It focuses on their occurrence and association with the extent of tibiotalar dislocation of the ankle joint on the trauma X-ray and its relation to the choice of surgery.

MATERIAL AND METHODS:
The cohort of a total of 824 patients with type B and C fractures according to Weber classification was followed up for 9 years. The cohort consisted of 403 (48.9%) men and 421 (51.1%) women. The exclusion criteria included associated talus fractures, calcaneus fractures and fractures of the other bones of the foot. The studied data were obtained retrospectively from medical documentation and by evaluation of trauma X-rays and X-rays obtained during the postoperative checks.
The ankle fractures were classified based on the Weber classification and the basic epidemiologic data (age and gender), type of fracture and extent of tibiotalar dislocation of ankle fractures on the trauma X-ray were evaluated. Posttraumatic ankle dislocation was divided into tibiotalar dislocation > 10 mm, tibiotalar dislocation < 10 mm and the group with regular ankle joint. When evaluating the treatment method, the cohort was divided into three groups: Group 1 with one-stage osteosynthesis, Group 2 with temporary K-wire transfixation or external fixation and subsequent secondary conversion to internal osteosynthesis, and Group 3 with definitive transfixation or external fixation of the ankle.
The results were statistically evaluated using the Pearson s chi-square test, or the Fisher s exact test for low frequencies.
A multivariant logistic regression model was created to identify statistically significant factors contributing to the development of synostosis. The results with the p-value < 0.05 were considered statistically significant.

RESULTS:
In the whole cohort, the synostosis of distal tibiofibular joint was observed in a total of 131 (15.9%) patients. In men it was in 85 (21.1%) cases and in women in 46 (10.9%) cases, which was statistically significant (p < 0.0001). There was a statistically significant difference (p = 0.0020) between the mean age in the group of patients with synostosis (54.4 years) and the mean age in the group of patients without synostosis (49.1 years).
Complete distal tibiofibular synostoses were found in 78 (12.7%) fractures classified as type B according to the Weber classification and in 53 (25.5%) type C fractures. When taking into account the gender, synostoses occurred more frequently in men in both types of fractures classified based on the Weber classification, only in type C fractures no statistical significance was established (p = 0.3026).
Various size of posttraumatic tibiotalar dislocation was present in both types of fractures. The group with less severe type B ankle fractures showed a statistically significant dominance of synostosis development in cases with large tibiotalar dislocation of more than 10 mm (p

Keywords: ankle fracture, distal tibiofibular synostosis, ankle joint dislocation, Weber classification, acute surgery, delayed surgery

Published: February 15, 2022  Show citation