Andreas F Dalen, Martin G Gregersen, Aleksander L Skrede, Øystein Bjelland, Tor Åge Myklebust, Fredrik A Nilsen, Marius Molund
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引用次数: 0
Abstract
Background: Conventionally, transsyndesmotic fibula fractures with concomitant signs of deltoid ligament injury have been considered unstable and thus treated operatively. Recent studies have indicated that partial deltoid ligament rupture is common and may allow for nonoperative treatment of stress-unstable ankles if normal tibiotalar alignment is obtained in the weightbearing position. Biomechanical support for this principle is scarce. The purpose of this study was to evaluate the biomechanical effects of gradually increasing deltoid ligament injury in transsyndesmotic fibula fractures.
Methods: Fifteen cadaveric ankle specimens were tested using an industrial robot. All specimens were tested in 4 states: native, SER2, SER4a, and SER4b models. Ankle stability was measured in lateral translation, valgus, and internal and external rotation stress in 3 talocrural joint positions: 20 degrees plantarflexion, neutral, and 10 degrees dorsiflexion. Talar shift and talar valgus tilt in the talocrural joint was measured using fluoroscopy.
Results: In most tests, SER2 and SER4a models resulted in a small instability increase compared to native joints and thus were deemed stable according to our predefined margins. However, SER4a models were unstable when tested in the plantarflexed position and for external rotation in all positions. In contrast, SER4b models had large-magnitude instability in all directions and all tested positions and were thus deemed unstable.
Conclusion: This study demonstrated substantial increases in instability between the SER4a and SER4b states. This controlled cadaveric simulation suggests a significant ankle-stabilizing role of the deep posterior deltoid after oblique transsyndesmotic fibular fracture and transection of the superficial and anterior deep deltoid ligaments.
Clinical relevance: The study provides new insights into how the heterogenicity of deltoid ligament injuries can affect the natural stability of the ankle after Weber B fractures. These findings may be useful in developing more targeted and better treatment strategies.
期刊介绍:
Foot & Ankle International (FAI), in publication since 1980, is the official journal of the American Orthopaedic Foot & Ankle Society (AOFAS). This monthly medical journal emphasizes surgical and medical management as it relates to the foot and ankle with a specific focus on reconstructive, trauma, and sports-related conditions utilizing the latest technological advances. FAI offers original, clinically oriented, peer-reviewed research articles presenting new approaches to foot and ankle pathology and treatment, current case reviews, and technique tips addressing the management of complex problems. This journal is an ideal resource for highly-trained orthopaedic foot and ankle specialists and allied health care providers.
The journal’s Founding Editor, Melvin H. Jahss, MD (deceased), served from 1980-1988. He was followed by Kenneth A. Johnson, MD (deceased) from 1988-1993; Lowell D. Lutter, MD (deceased) from 1993-2004; and E. Greer Richardson, MD from 2005-2007. David B. Thordarson, MD, assumed the role of Editor-in-Chief in 2008.
The journal focuses on the following areas of interest:
• Surgery
• Wound care
• Bone healing
• Pain management
• In-office orthotic systems
• Diabetes
• Sports medicine