Frederick Michels1, Giovanni Matricali2,3,4, Stephane Guillo5, Frederik Vanrietvelde6, Hans Pottel7, Filip Stockmans8,9. 1. Orthopaedic Department, AZ Groeninge, President Kennedylaan 4, 8500, Kortrijk, Belgium. frederick_michels@hotmail.com. 2. Department of Development and Regeneration, KU Leuven, Leuven, Belgium. 3. Department of Orthopaedics, Foot and Ankle Unit, University Hospitals Leuven, KU Leuven, Leuven, Belgium. 4. Institute of Orthopaedic Research and Training, KU Leuven, Leuven, Belgium. 5. Orthopaedic Department, Mérignac Sports Clinic, 2, Rue Georges Negrevergne, 33700, Mérignac, France. 6. Radiology Department, AZ Groeninge Kortrijk, President Kennedylaan 4, 8500, Kortrijk, Belgium. 7. Department of Public Health and Primary Care, Catholic University Leuven, Kortrijk, Belgium. 8. Orthopaedic Department, AZ Groeninge, President Kennedylaan 4, 8500, Kortrijk, Belgium. 9. Department of Development and Regeneration, Faculty of Medicine, University of Leuven Campus Kortrijk, Etienne Sabbelaan 53, 8500, Kortrijk, Belgium.
Abstract
PURPOSE: A bone tunnel is often used during the reconstruction of the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL). The purpose of this study is to compare proposed directions for drilling this fibular tunnel and to assess potential tunnel length, using a 5-mm-diameter tunnel and surrounding bone. METHODS: Anonymous DICOM data from spiral CT-scan images of the ankle were obtained from 12 Caucasian patients: 6 females and 6 males. Virtual tunnels were generated in a 3D bone model with angles of 30°, 45°, 60° and 90° in relation to the fibular long axis. Several measurements were performed: distance from entrance to perforation of opposing cortex, shortening of the tunnel, distance from tunnel centre to bone surface. RESULTS: A tunnel in a perpendicular direction resulted in an average possible tunnel length of 16.8 (± 2.7) mm in the female group and 20.3 (± 3.4) mm in the male group. A tunnel directed at 30° offered the longest length: 30.9 (± 2.5) mm in the female group and 34.4 (± 2.9) mm in the male group. The use of a 5-mm-diameter tunnel in a perpendicular direction caused important shortening of the tunnel at the entrance in some cases. The perpendicular tunnel was very near to the digital fossa while the most obliquely directed tunnels avoided this region. CONCLUSION: An oblique tunnel allows for a longer tunnel and avoids the region of the digital fossa, thereby retaining more surrounding bone. In addition, absolute values of tunnel length are given, which can be useful when considering the use of certain implants. We recommend drilling an oblique fibular tunnel when reconstructing the ATFL and CFL.
PURPOSE: A bone tunnel is often used during the reconstruction of the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL). The purpose of this study is to compare proposed directions for drilling this fibular tunnel and to assess potential tunnel length, using a 5-mm-diameter tunnel and surrounding bone. METHODS: Anonymous DICOM data from spiral CT-scan images of the ankle were obtained from 12 Caucasian patients: 6 females and 6 males. Virtual tunnels were generated in a 3D bone model with angles of 30°, 45°, 60° and 90° in relation to the fibular long axis. Several measurements were performed: distance from entrance to perforation of opposing cortex, shortening of the tunnel, distance from tunnel centre to bone surface. RESULTS: A tunnel in a perpendicular direction resulted in an average possible tunnel length of 16.8 (± 2.7) mm in the female group and 20.3 (± 3.4) mm in the male group. A tunnel directed at 30° offered the longest length: 30.9 (± 2.5) mm in the female group and 34.4 (± 2.9) mm in the male group. The use of a 5-mm-diameter tunnel in a perpendicular direction caused important shortening of the tunnel at the entrance in some cases. The perpendicular tunnel was very near to the digital fossa while the most obliquely directed tunnels avoided this region. CONCLUSION: An oblique tunnel allows for a longer tunnel and avoids the region of the digital fossa, thereby retaining more surrounding bone. In addition, absolute values of tunnel length are given, which can be useful when considering the use of certain implants. We recommend drilling an oblique fibular tunnel when reconstructing the ATFL and CFL.
Authors: S Guillo; T Bauer; J W Lee; M Takao; S W Kong; J W Stone; P G Mangone; A Molloy; A Perera; C J Pearce; F Michels; Y Tourné; A Ghorbani; J Calder Journal: Orthop Traumatol Surg Res Date: 2013-11-20 Impact factor: 2.256