A novel classification of lateral malleolus morphological characteristics based on three-dimensional computed tomography reconstruction.

BACKGROUND: The study was to establish a novel classification of the morphological characteristics of fibula anterior-inferior margin (FAIM), which was reported in few studies. METHODS: The 501 images with three-dimensional computed tomography (3D CT) reconstruction were reviewed retrospectively. The width, height, thickness, long axis, short axis, and lateral malleolus angle were measured. RESULTS: The FAIM was divided into Angular, Flat, and Arc. The Flat has no distinct fibular obscure tubercles (FOT). The short axis of Angular and Arc were more significant than the Flat (P < 0. 05). The height of left was larger than the right, but short axis was less than it (P < 0.05). The height and short axis of males were larger than the females (P < 0.05). CONCLUSIONS: A novel classification (the Angular, Flat and Arc) of FAIM was identified based on lateral malleolus morphology, and it suggested that not all have obvious FOT. LEVEL OF EVIDENCE: Level Ⅲ, retrospective study.

Association between the distal tibiofibular syndesmosis morphology classification and ankle osteoarthritis: a retrospective study.

BACKGROUND: Syndesmosis injury is proposed to contribute to ankle stability and osteoarthritis (OA). However, whether distal tibiofibular syndesmosis structure is closely related to ankle OA is unclear. We hypothesized that different DTS morphology classifications would affect the biomechanics properties in ankle OA. The study aimed to determine the association between the distal tibiofibular syndesmosis (DTS) morphological classification and ankle OA. METHODS: This is a retrospective study examining imaging data of 147 patients (87 males and 60 females) with ankle OA. Magnetic resonance imaging was used to access the DTS morphological classification, according to measuring various parameters. Joint space narrowing and osteophytes were measured using ankle weight-bearing radiography. The classification and parameters were analyzed to determine the relationship between the syndesmosis classification and the abnormality of ankle OA. RESULTS: Five morphological classifications of the DTS, including Chevron (19.6%), Widow's peak (16.2%), Flat (22.3%), Trapezoid (32.0%), and Crescent (19.6%), were shown. There were statistical differences between DTS classification and tibial angle surface angle (TAS) (P = .009) and talar tilt angle (TTA) (P = .014). The TAS (degree) of the Crescent (86.47 ± 3.21) was less than Chevron (88.75 ± 2.72) (P = .006), Widow's peak (89.26 ± 3.15) (P = .001), Flat (88.83 ± 3.62) (P = .003) and Trapezoid (88.11 ± 2.62) (P = .041), respectively. The TTA (degree) of Crescent (86.83 ± 5.30) was less than Chevron (89.28 ± 2.46) and Widow's peak (89.82 ± 3.41). The men were greater than women for TAS (P = .008) and angle (P = .003), which are consistent with osteophyte (P = .019) and the modified Kellgren-Lawrence grades (P = .041) between gender. CONCLUSIONS: DTS morphological classification might affect the biomechanics properties in TAS and TTA in ankle OA. In clinical practice, surgeons should pay attention to the effects of DTS on ankle OA. LEVEL OF EVIDENCE: Level III, retrospective study.