Relationship between distal tibial transosseous wires and ankle joint synovium: A cadaveric analysis

Abstract

Background: Distal tibial fractures are managed with external fixation techniques such as Ilizarov to prevent soft-tissue-related complications. In spite of adequate care in wire placement techniques, some cases experience synovitis of ankle joint, stiffness of joint due to pin-tract infections, and deep-seated infection. The accurate description of the ankle joint capsular and synovial recess anatomy is still not clear. The purpose of our study was to study the accuracy of the available guidelines for wire insertion by identifying the relationship between the ankle capsular attachments and the wires in an Indian population. Materials and Methods: 1.8-mm Ilizarov transosseous wires were inserted percutaneously through the distal fibula to tibia from posterolateral to anteromedial direction 2 cm above the joint line in 20 embalmed cadaveric limbs. Dissection of the ankle joint was performed after a dye was introduced into the joint capsule to look for the extent of synovium from the joint line, medial malleolus, and lateral malleolus by the visible bulging and color change of the membrane. Distance from the wire to the synovial extensions distally was measured with a vernier caliper. Results: The mean distance of synovial extension from the joint line, medial malleolus, and lateral malleolus were 20.2 mm, 30.8 mm, and 41.4 mm, respectively. Distal wire-to-synovial extension distance anteriorly was ± 0.2 mm. Wire-to-joint line distance after dissection was 20 mm. The proximal synovial extension was found to be in the 101% from the joint line to the wire. Conclusion: The synovial extensions were found to be close to the distal tibial transosseous wires. A minimum distance of 2.5–3 cm from the joint line proximally should be the safe extent for passing the wires to prevent the risk of synovitis.