Morphological study of proximal fibular fractures with concomitant tibial plateau fractures：an investigation of 223 cases

Purpose This study aimed to systematically characterize the morphological patterns of proximal fibular fractures occurring concurrently with tibial plateau fractures. Methods Data were retrospectively collected from a Level-1 trauma center between January 2011 and January 2024 by querying hospital information and picture archiving and communication systems with keywords "tibial plateau fracture" and "fibular fracture" or "fibular head fracture". Radiographic morphology was evaluated using standard anteroposterior radiographs and three-dimensional computed tomography (3D-CT), categorizing proximal fibular fractures into 13 predefined morphological patterns. Descriptive data, including fracture location, number of fragments, and degree of displacement, were recorded and classified. The distribution patterns of proximal fibular fractures were further correlated with the tibial plateau fractures, categorized according to the CT-based three-column classification system. Logistic regression analysis was conducted to identify the associations between specific tibial plateau fracture subtypes and proximal fibular fracture patterns. Results A total of 223 eligible patients (123 males) were included in the analysis. Group I, II, and III proximal fibular fractures were observed in 63 (28.3%), 121 (54.3%), and 39 (17.4%) patients, respectively. Within group II, subtype II3p was the predominant fracture pattern, occurring in 62 patients (51.3%). Subtypes II1p(L), II2p(L + P), and III3 were not identified in the cohort. Group I fractures did not occur in posterior column or combined lateral and posterior column fractures. Group II fractures were absent in isolated lateral column or combined medial and lateral column fractures. Group III fractures exclusively presented with combined lateral and posterior column or three-column fractures. Logistic regression indicated that group I proximal fibular fractures were significantly more associated with isolated medial column tibial plateau fractures, whereas group II fractures were significantly associated with lateral-posterior and medial-posterior column fractures compared to three-column fractures. Conversely, group III proximal fibular fractures were significantly more common with three-column fractures than with lateral-posterior column fractures. Conclusions The morphological diversity observed in proximal fibular fractures underscores the complexity and heterogeneity of concomitant tibial plateau fractures. Further clinical and biomechanical investigations are warranted to elucidate the pathomechanics underlying comminuted fibular fractures associated with tibial plateau injuries.