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Category: Trauma; Ankle Introduction/Purpose: Fibular fractures with signs of concomitant deltoid ligament injury have been operated on with plate and screw fixation of the fibula for decades. More recently, clinical studies have suggested that some fibular fractures have only partial deltoid ligament injury and that the deep posterior tibiotalar ligament may be intact (SER4a), allowing for nonoperative treatment. The purpose was to determine whether fibula fracture fixation using plate and screws improves stability and restores normal joint kinematics in such fractures. It was hypothesised that fixation of the fibula fracture does not add significantly to the stability of SER4a models or restore normal joint kinematics. Methods: Fifteen cadaveric foot and ankle specimens underwent biomechanical testing using a six-degrees-of-freedom force- movement robotic arm in three states: intact joint, SER4a model (anterior inferior tibiofibular ligament sectioned + oblique trans syndesmotic fibular osteotomy + superficial layer of deltoid ligament sectioned + deep anterior tibiotalar ligament sectioned) and SER4a model + plate and screw fixation of the fibula. Joint stability was measured in lateral translation, valgus, and talar internal- and external rotation in three talocrural joint positions: 20° plantarflexion, neutral, and 10° dorsiflexion. Fluoroscopy was used to measure isolated talar lateralisation and talar tilt. The foot was rigidly fixed to a custom pedestal, while the tibia was rigidly fixed to the robot arm through a load cell. Talar lateral translation at neutral ankle position was the primary outcome. Results: Fixation of the fibular fracture reduced lateral translation by 0.16 millimetres (P =.101) at neutral ankle position (See Figure 1). In general, the tests for lateral translation and valgus showed no differences between the SER4a models and the SER4a models with fibular fracture fixation. As for talar internal rotation, the fixation only slightly increased stability. But, when the talus was externally rotated, the fixation provided stability. Although the fixation improved stability during rotations, it did not fully restore the native ankle kinematics. Conclusion: The results suggest that plate and screw fixation of the fibular fracture does not significantly reduce instability or restore intact joint stability in SER4a models. These results support the nonoperative treatment of these fractures, as suggested by previous clinical studies. [ABSTRACT FROM AUTHOR]

Category: Ankle Arthritis; Ankle Introduction/Purpose: Total ankle arthroplasty (TAA) with severe varus ankle deformity is balanced in the coronal plane by releasing medial soft tissue constraints. There are no previous reports examining the impacts of TAA with concomitant release of the deltoid. Progressive talar tilt and progressive collapsing foot deformity were evaluated. Methods: A retrospective review included patients undergoing TAA with confirmed preoperative varus deformity. Patients underwent complete soft tissue release of the deltoid ligament complex. Pre- and post-operative weightbearing radiographs quantified Meary's angle, lateral talo-1st metatarsal angle, calcaneal pitch, talar coronal alignment, and the lateral distal tibial angle. The primary endpoints were degrees of coronal plane correction, longitudinal arch position, and complication rates. Results: Thirty-two patients were included with median 12.5 month follow-up. Coronal plane alignment and VAS pain scores improved significantly in all patients, and statistical analysis revealed that complete deltoid ligament release had no bearing on calcaneal pitch and Meary's angle at final follow-up. Posterior tibial tenotomy was performed on 3 (9.3%) patients. Median coronal plane alignment correction averaged 17.5° improvement (X2(2)= 50.358, P<.001) from 19.5° varus (11.2-24.5°) to 2.0° varus (0.5- 3.5°)(P <.001). Two degrees of coronal plane varus alignment without tilt progression (0.6-3.4°)(P <.001) was maintained through follow-up. Final calcaneal pitch of 18.2° (14.4-23.2°) mirrored initial median measurement of 18.3° (15.7-21.1°). No significant differences were found between Meary's angle measurements at any time points (P=.568). Eight of 32 patients had complications with five requiring further ankle surgery. Conclusion: Complete release of the deltoid ligament may improve coronal malalignment when performing TAA. Release did not lead to radiographic or clinical medial instability, valgus talar tilt, or medial arch collapse. [ABSTRACT FROM AUTHOR]