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Bolt fixation for syndesmotic injuries
Injury, Int. J. Care Injured 40 (2009) 1176–1179
Contents lists available at ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Bolt fixation for syndesmotic injuries J. De Vil a,*, F. Bonte a, H. Claes b, W. Bongaerts a, K. Verstraete b, R. Verdonk a a b
Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, De Pintelaan 185, B 9000 Ghent, Belgium Department of Radiology, Ghent University Hospital, Ghent, Belgium
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 17 February 2009
We performed a retrospective study of 28 patients who underwent bolt fixation for a syndesmotic injury to the ankle. The mean follow-up period was 66 months (range: 24–139 months). The results of surgery were assessed clinically and radiographically. Overall, this fixation device was found to adequately stabilise the syndesmosis during healing. Radiologically accurate syndesmosis reduction was achieved in 26 patients. The mean AOFAS score was 86 (range: 33–100). The majority of patients were very satisfied with the overall result. It is a simple and quick operative procedure providing reliable syndesmotic reduction. The material should not be removed prior to walking. The only drawback is the greater need for removal in the event of local symptoms. ß 2009 Elsevier Ltd. All rights reserved.
Keywords: Syndesmosis Syndesmotic fixation Distal tibiofibular ligaments
Syndesmotic injury of the ankle commonly occurs secondary to an external rotational force applied to the ankle joint.7,18 Most cases of diastasis are associated with fractures of the tibia and fibula.4 Multiple techniques have been described for the stabilisation of syndesmotic disruptions. In our department, syndesmotic bolt fixation (Francemed, Bagneux, France) has been used for more than 60 years. The device was developed by Verbrugge in 1949.19 Although some minor modifications have been made over the years, the basic concept has remained unchanged. The present study was designed to evaluate the clinical and radiographic outcome and the complications that may occur with this device. Materials and methods Patient population In this retrospective study patients who had undergone a bolt fixation for a syndesmotic rupture between 1996 and 2005 were included. The minimum follow-up period was 2 years. In November and December 2007, 28 patients (10 females and 18 males) were available for a clinical and radiographic follow-up. The mean age at the time of surgery was 44 years (range: 16–65 years). Two patients were diabetics. Operative technique and postoperative care Any associated fractures were managed first. The integrity of the syndesmosis was then evaluated with the use of intra-
* Corresponding author. Tel.: +32 9 3326887; fax: +32 9 3323417. E-mail address: [email protected] (J. De Vil). 0020–1383/$ – see front matter ß 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2009.02.013
operative fluoroscopy.12 Syndesmotic disruption was presumed with the widening of the tibiofibular clear space of more than 3 mm. Fluoroscopy was also required to ensure that the device was inserted at the proper level. The device used in these patients was a fully threaded bolt, 3 mm in diameter (Fig. 1), provided with two semi-rigid hooks (Fig. 2) on the distal tibial side and with a washer and nut on the fibular side. The bolt was placed between the fibula and tibia at the level of the syndesmosis. The injury was stabilised with this device between the hooks on the tibial side and the washer/nut on the fibular side. The bolt fixed and compressed the syndesmosis. When the hooks began to deform, adequate compression was reached. A small skin incision was made over the fibula at the level of the syndesmosis. A hole, 3 mm in diameter, was drilled from the fibula to the tibia, parallel to the ankle joint line, through the medial border of the tibia. We used a twist drill, 3 mm in diameter (Fig. 3), provided with a screw connection to fit the pin driver. A second, small, skin incision was made over the tibia. Drilling was continued through the medial skin incision. After drilling the hole, the drill bit was left in place. It was disconnected from the drill and the pin driver (Fig. 4) was screwed onto the drill. The drill and pin driver were pulled from the lateral to the medial side. When the pin driver had completely penetrated the medial hole, it was disconnected from the drill and the bolt was screwed onto the pin driver, which was then pulled to the lateral side. The hooks of the bolt were carefully hidden under the skin on the medial side of the tibia. On the lateral side the pin driver was disconnected from the bolt. The washer and nut were screwed onto the bolt, until they were hidden under the skin. Under fluoroscopic guidance, tightening was continued with the foot in dorsiflexion until syndesmotic reduction was achieved. Care was taken to avoid
J. De Vil et al. / Injury, Int. J. Care Injured 40 (2009) 1176–1179
Fig. 1. Bolt.
deformation of the tibial hooks. Finally, the lateral end of the bolt was cut near the nut (Figs. 5 and 6). Postoperatively, the patients were immobilised in a short leg cast and prohibited from bearing weight on the affected ankle for 6 weeks. The material was only removed if it caused discomfort. The patients were evaluated by an independent examiner, who had not been involved in the surgery. Clinical assessment The questionnaire used was based on the AOFAS ankle– hindfoot rating system.8 The patients were questioned regarding pain, limitations of activity and overall satisfaction. The range of motion was measured with a goniometer and compared with the contralateral side.
Fig. 2. Hooks of the bolt.
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Fig. 3. Drill.
Radiographic assessment The radiographic assessment included three views of the ankle joint (anteroposterior, mortise and lateral) with the patient standing on both feet. These views are required for the assessment of the ankle mortise and distal tibiofibular syndesmosis.5,16 The radiographs were assessed with respect to the following criteria: presence of talar tilt or shift and syndesmotic bolt placement. The projected level of syndesmotic bolt placement was measured between the distal articular surface of the tibia and the centre of the entry point of the bolt in the lateral tibial cortex. We defined transsyndesmotic bolt placement to be within 2 cm from the tibial plafond and a suprasyndesmotic bolt placement to be more than 2 cm, but within 5 cm, from the tibial plafond.9 The talar tilt was defined as the angle between the distal articular surface of the tibia and the talar surface exceeding 158 on the mortise view. Radiographic loss of reduction was assumed if the clear space between tibia and fibula at the fibular notch exceeded 6 mm, or if less than 1 mm overlap was present between the distal tibia and fibula on the mortise view.5 Statistical analysis was performed using the Statistical Package for Social Science (SPSS version 15). Institutional review board approval was obtained for the retrospective review of the data.
Fig. 4. Drill and pin driver.
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J. De Vil et al. / Injury, Int. J. Care Injured 40 (2009) 1176–1179 Table 1 Ranges of motion.
Dorsiflexion Plantarflexion
Operated side
Not operated side
138(0–208) 378(10–608)
168(0–208) 448(20–608)
syndesmotically in nine patients and suprasyndesmotically in 19 patients. The mean level of bolt placement was 28 mm from the tibial plafond. The mean AOFAS score was 86 (range: 33–100). Twenty-three patients were very satisfied with the overall result. Clinical examination showed pain at the inferior tibiofibular joint in four patients. Ranges of motion are outlined in Table 1. Radiographic loss of reduction was noted in two patients who complained of pain at the inferior tibiofibular joint. One of these patients had a transsyndesmotic bolt placement; the other a suprasyndesmotic bolt placement. Complications included skin irritation or hardware penetration on the lateral side, which necessitated removal in five patients. Two of the patients were diabetics. No other major complications were encountered. Discussion
Fig. 5. Preoperative radiograph.
Results The mean follow-up duration from the time of surgery was 66 months (range: 24–139 months). The device was placed trans-
Adequate reduction of syndesmotic ruptures is essential to prevent late osteoarthritis and dysfunction of the ankle. Ramsey and Hamilton showed that 1 mm of lateral displacement of the talus reduced the tibiotalar contact area by 42%, producing increased contact stress and risk of ankle osteoarthritis.17 The best results are achieved after accurate reduction of the syndesmosis, and a greater increase in the width of the syndesmosis is associated with a worse result. Syndesmosis widening of more than 1.5 mm is unacceptable.3 Many techniques have been described for the stabilisation of syndesmotic disruptions, we have been using bolt fixation for 60 years, however, the most widely used method remains screw stabilisation.13,14 The optimal level for the syndesmosis fixation is not clearly defined. In their biomechanical study, McBryde et al. suggested that the optimal placement should be at 2 cm above the tibiotalar joint.10 However, Miller et al. concluded from their study on cadaveric legs that fixation at 5 cm provided significantly more holding strength than fixation at 2 cm.11 Clinically, there does not appear to be any significant difference between the suprasyndesmotic and the transsyndesmotic positions.9 The literature remains divided regarding the necessity of hardware removal. Only few clinical studies exist. Fixation with a 3.5- or 4.5-mm screw provides rigid fixation of the distal tibiofibular joint, where physiological micro-movement has been shown to occur.2 Therefore, leaving it in place may contribute to abnormal ankle movement, which, in turn, may result in loosening6 or fatigue fracture of the screw.1,15 Routine removal of the implant requires a second operative procedure with associated surgical morbidity and cost. The bolt we used is much less rigid and allows micromovement of the joint. It does not require removal prior to walking. Nevertheless, in five patients the device had to be removed due to the occurrence of local symptoms. When classical syndesmotic screws are used, a lower percentage of screws have to be removed (7%).14 Conclusion
Fig. 6. Postoperative radiograph.
Our findings suggest that bolt fixation efficiently stabilises the syndesmosis during healing. It is a simple and quick operative procedure providing reliable syndesmotic reduction. The device
J. De Vil et al. / Injury, Int. J. Care Injured 40 (2009) 1176–1179
does not need to be removed prior to walking. The only drawback is the greater need for removal in the event of local symptoms. Conflict of interest The authors declare to have no conflict of interest. References 1. Bell DP, Wong MK. Syndesmotic screw fixation in Weber C ankle injuries— should the screw be removed before weight bearing? Injury 2006;37(9): 891–8. 2. Beumer A, Valstar ER, Garling EH, et al. Kinematics of the distal tibiofibular syndesmosis: radiostereometry in 11 normal ankles. Acta Orthop Scand 2003;74(3):337–43. 3. Chissell HR, Jones J. The influence of a diastasis screw on the outcome of Weber type-C ankle fractures. J Bone Joint Surg Br 1995;77(3):435–8. 4. Edwards Jr GS, DeLee JC. Ankle diastasis without fracture. Foot Ankle 1984;4(6):305–12. 5. Harper MC, Keller TS. A radiographic evaluation of the tibiofibular syndesmosis. Foot Ankle 1989;10(3):156–60. 6. Heim D, Heim U, Regazzoni P. Malleolar fractures with ankle joint instability— experience with the positioning screw. Unfallchirurgie 1993;19(5):307–12. 7. Hopkinson WJ, St Pierre P, Ryan JB, Wheeler JH. Syndesmosis sprains of the ankle. Foot Ankle 1990;10(6):325–30.
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8. Kitaoka HB, Alexander IJ, Adelaar RS, et al. Clinical rating systems for the anklehindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int 1994;15(7):349–53. 9. Kukreti S, Faraj A, Miles JN. Does position of syndesmotic screw affect functional and radiological outcome in ankle fractures? Injury 2005;36(9):1121–4. 10. McBryde A, Chiasson B, Wilhelm A, et al. Syndesmotic screw placement: a biomechanical analysis. Foot Ankle Int 1997;18(5):262–6. 11. Miller RS, Weinhold PS, Dahners LE. Comparison of tricortical screw fixation versus a modified suture construct for fixation of ankle syndesmosis injury: a biomechanical study. J Orthop Trauma 1999;13(1):39–42. 12. Mizel MS. Technique tip: a revised method of the Cotton test for intra-operative evaluation of syndesmotic injuries. Foot Ankle Int 2003;24(1):86–7. 13. Monga P, Kumar A, Simons A, Panikker V. Management of distal tibio-fibular syndesmotic injuries: a snapshot of current practice. Acta Orthop Belg 2008; 74(3):365–9. 14. Moore Jr JA, Shank JR, Morgan SJ, Smith WR. Syndesmosis fixation: a comparison of three and four cortices of screw fixation without hardware removal. Foot Ankle Int 2006;27(8):567–72. 15. Needleman RL, Skrade DA, Stiehl JB. Effect of the syndesmotic screw on ankle motion. Foot Ankle 1989;10(1):17–24. 16. Pneumaticos SG, Noble PC, Chatziioannou SN, Trevino SG. The effects of rotation on radiographic evaluation of the tibiofibular syndesmosis. Foot Ankle Int 2002;23(2):107–11. 17. Ramsey PL, Hamilton W. Changes in tibiotalar area of contact caused by lateral talar shift. J Bone Joint Surg Am 1976;58(3):356–7. 18. Rasmussen O. Stability of the ankle joint. Analysis of the function and traumatology of the ankle ligaments. Acta Orthop Scand Suppl 1985;211:1–75. 19. Verbrugge J. L’oste´otomie et le retournement temporaires du pe´rone´ dans la voie d’abord du cou-de-pied. Acta Orthop Belg 1949;5:195–8.
Contents lists available at ScienceDirect
Injury journal homepage: www.elsevier.com/locate/injury
Bolt fixation for syndesmotic injuries J. De Vil a,*, F. Bonte a, H. Claes b, W. Bongaerts a, K. Verstraete b, R. Verdonk a a b
Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, De Pintelaan 185, B 9000 Ghent, Belgium Department of Radiology, Ghent University Hospital, Ghent, Belgium
A R T I C L E I N F O
A B S T R A C T
Article history: Accepted 17 February 2009
We performed a retrospective study of 28 patients who underwent bolt fixation for a syndesmotic injury to the ankle. The mean follow-up period was 66 months (range: 24–139 months). The results of surgery were assessed clinically and radiographically. Overall, this fixation device was found to adequately stabilise the syndesmosis during healing. Radiologically accurate syndesmosis reduction was achieved in 26 patients. The mean AOFAS score was 86 (range: 33–100). The majority of patients were very satisfied with the overall result. It is a simple and quick operative procedure providing reliable syndesmotic reduction. The material should not be removed prior to walking. The only drawback is the greater need for removal in the event of local symptoms. ß 2009 Elsevier Ltd. All rights reserved.
Keywords: Syndesmosis Syndesmotic fixation Distal tibiofibular ligaments
Syndesmotic injury of the ankle commonly occurs secondary to an external rotational force applied to the ankle joint.7,18 Most cases of diastasis are associated with fractures of the tibia and fibula.4 Multiple techniques have been described for the stabilisation of syndesmotic disruptions. In our department, syndesmotic bolt fixation (Francemed, Bagneux, France) has been used for more than 60 years. The device was developed by Verbrugge in 1949.19 Although some minor modifications have been made over the years, the basic concept has remained unchanged. The present study was designed to evaluate the clinical and radiographic outcome and the complications that may occur with this device. Materials and methods Patient population In this retrospective study patients who had undergone a bolt fixation for a syndesmotic rupture between 1996 and 2005 were included. The minimum follow-up period was 2 years. In November and December 2007, 28 patients (10 females and 18 males) were available for a clinical and radiographic follow-up. The mean age at the time of surgery was 44 years (range: 16–65 years). Two patients were diabetics. Operative technique and postoperative care Any associated fractures were managed first. The integrity of the syndesmosis was then evaluated with the use of intra-
* Corresponding author. Tel.: +32 9 3326887; fax: +32 9 3323417. E-mail address: [email protected] (J. De Vil). 0020–1383/$ – see front matter ß 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2009.02.013
operative fluoroscopy.12 Syndesmotic disruption was presumed with the widening of the tibiofibular clear space of more than 3 mm. Fluoroscopy was also required to ensure that the device was inserted at the proper level. The device used in these patients was a fully threaded bolt, 3 mm in diameter (Fig. 1), provided with two semi-rigid hooks (Fig. 2) on the distal tibial side and with a washer and nut on the fibular side. The bolt was placed between the fibula and tibia at the level of the syndesmosis. The injury was stabilised with this device between the hooks on the tibial side and the washer/nut on the fibular side. The bolt fixed and compressed the syndesmosis. When the hooks began to deform, adequate compression was reached. A small skin incision was made over the fibula at the level of the syndesmosis. A hole, 3 mm in diameter, was drilled from the fibula to the tibia, parallel to the ankle joint line, through the medial border of the tibia. We used a twist drill, 3 mm in diameter (Fig. 3), provided with a screw connection to fit the pin driver. A second, small, skin incision was made over the tibia. Drilling was continued through the medial skin incision. After drilling the hole, the drill bit was left in place. It was disconnected from the drill and the pin driver (Fig. 4) was screwed onto the drill. The drill and pin driver were pulled from the lateral to the medial side. When the pin driver had completely penetrated the medial hole, it was disconnected from the drill and the bolt was screwed onto the pin driver, which was then pulled to the lateral side. The hooks of the bolt were carefully hidden under the skin on the medial side of the tibia. On the lateral side the pin driver was disconnected from the bolt. The washer and nut were screwed onto the bolt, until they were hidden under the skin. Under fluoroscopic guidance, tightening was continued with the foot in dorsiflexion until syndesmotic reduction was achieved. Care was taken to avoid
J. De Vil et al. / Injury, Int. J. Care Injured 40 (2009) 1176–1179
Fig. 1. Bolt.
deformation of the tibial hooks. Finally, the lateral end of the bolt was cut near the nut (Figs. 5 and 6). Postoperatively, the patients were immobilised in a short leg cast and prohibited from bearing weight on the affected ankle for 6 weeks. The material was only removed if it caused discomfort. The patients were evaluated by an independent examiner, who had not been involved in the surgery. Clinical assessment The questionnaire used was based on the AOFAS ankle– hindfoot rating system.8 The patients were questioned regarding pain, limitations of activity and overall satisfaction. The range of motion was measured with a goniometer and compared with the contralateral side.
Fig. 2. Hooks of the bolt.
1177
Fig. 3. Drill.
Radiographic assessment The radiographic assessment included three views of the ankle joint (anteroposterior, mortise and lateral) with the patient standing on both feet. These views are required for the assessment of the ankle mortise and distal tibiofibular syndesmosis.5,16 The radiographs were assessed with respect to the following criteria: presence of talar tilt or shift and syndesmotic bolt placement. The projected level of syndesmotic bolt placement was measured between the distal articular surface of the tibia and the centre of the entry point of the bolt in the lateral tibial cortex. We defined transsyndesmotic bolt placement to be within 2 cm from the tibial plafond and a suprasyndesmotic bolt placement to be more than 2 cm, but within 5 cm, from the tibial plafond.9 The talar tilt was defined as the angle between the distal articular surface of the tibia and the talar surface exceeding 158 on the mortise view. Radiographic loss of reduction was assumed if the clear space between tibia and fibula at the fibular notch exceeded 6 mm, or if less than 1 mm overlap was present between the distal tibia and fibula on the mortise view.5 Statistical analysis was performed using the Statistical Package for Social Science (SPSS version 15). Institutional review board approval was obtained for the retrospective review of the data.
Fig. 4. Drill and pin driver.
1178
J. De Vil et al. / Injury, Int. J. Care Injured 40 (2009) 1176–1179 Table 1 Ranges of motion.
Dorsiflexion Plantarflexion
Operated side
Not operated side
138(0–208) 378(10–608)
168(0–208) 448(20–608)
syndesmotically in nine patients and suprasyndesmotically in 19 patients. The mean level of bolt placement was 28 mm from the tibial plafond. The mean AOFAS score was 86 (range: 33–100). Twenty-three patients were very satisfied with the overall result. Clinical examination showed pain at the inferior tibiofibular joint in four patients. Ranges of motion are outlined in Table 1. Radiographic loss of reduction was noted in two patients who complained of pain at the inferior tibiofibular joint. One of these patients had a transsyndesmotic bolt placement; the other a suprasyndesmotic bolt placement. Complications included skin irritation or hardware penetration on the lateral side, which necessitated removal in five patients. Two of the patients were diabetics. No other major complications were encountered. Discussion
Fig. 5. Preoperative radiograph.
Results The mean follow-up duration from the time of surgery was 66 months (range: 24–139 months). The device was placed trans-
Adequate reduction of syndesmotic ruptures is essential to prevent late osteoarthritis and dysfunction of the ankle. Ramsey and Hamilton showed that 1 mm of lateral displacement of the talus reduced the tibiotalar contact area by 42%, producing increased contact stress and risk of ankle osteoarthritis.17 The best results are achieved after accurate reduction of the syndesmosis, and a greater increase in the width of the syndesmosis is associated with a worse result. Syndesmosis widening of more than 1.5 mm is unacceptable.3 Many techniques have been described for the stabilisation of syndesmotic disruptions, we have been using bolt fixation for 60 years, however, the most widely used method remains screw stabilisation.13,14 The optimal level for the syndesmosis fixation is not clearly defined. In their biomechanical study, McBryde et al. suggested that the optimal placement should be at 2 cm above the tibiotalar joint.10 However, Miller et al. concluded from their study on cadaveric legs that fixation at 5 cm provided significantly more holding strength than fixation at 2 cm.11 Clinically, there does not appear to be any significant difference between the suprasyndesmotic and the transsyndesmotic positions.9 The literature remains divided regarding the necessity of hardware removal. Only few clinical studies exist. Fixation with a 3.5- or 4.5-mm screw provides rigid fixation of the distal tibiofibular joint, where physiological micro-movement has been shown to occur.2 Therefore, leaving it in place may contribute to abnormal ankle movement, which, in turn, may result in loosening6 or fatigue fracture of the screw.1,15 Routine removal of the implant requires a second operative procedure with associated surgical morbidity and cost. The bolt we used is much less rigid and allows micromovement of the joint. It does not require removal prior to walking. Nevertheless, in five patients the device had to be removed due to the occurrence of local symptoms. When classical syndesmotic screws are used, a lower percentage of screws have to be removed (7%).14 Conclusion
Fig. 6. Postoperative radiograph.
Our findings suggest that bolt fixation efficiently stabilises the syndesmosis during healing. It is a simple and quick operative procedure providing reliable syndesmotic reduction. The device
J. De Vil et al. / Injury, Int. J. Care Injured 40 (2009) 1176–1179
does not need to be removed prior to walking. The only drawback is the greater need for removal in the event of local symptoms. Conflict of interest The authors declare to have no conflict of interest. References 1. Bell DP, Wong MK. Syndesmotic screw fixation in Weber C ankle injuries— should the screw be removed before weight bearing? Injury 2006;37(9): 891–8. 2. Beumer A, Valstar ER, Garling EH, et al. Kinematics of the distal tibiofibular syndesmosis: radiostereometry in 11 normal ankles. Acta Orthop Scand 2003;74(3):337–43. 3. Chissell HR, Jones J. The influence of a diastasis screw on the outcome of Weber type-C ankle fractures. J Bone Joint Surg Br 1995;77(3):435–8. 4. Edwards Jr GS, DeLee JC. Ankle diastasis without fracture. Foot Ankle 1984;4(6):305–12. 5. Harper MC, Keller TS. A radiographic evaluation of the tibiofibular syndesmosis. Foot Ankle 1989;10(3):156–60. 6. Heim D, Heim U, Regazzoni P. Malleolar fractures with ankle joint instability— experience with the positioning screw. Unfallchirurgie 1993;19(5):307–12. 7. Hopkinson WJ, St Pierre P, Ryan JB, Wheeler JH. Syndesmosis sprains of the ankle. Foot Ankle 1990;10(6):325–30.
1179
8. Kitaoka HB, Alexander IJ, Adelaar RS, et al. Clinical rating systems for the anklehindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int 1994;15(7):349–53. 9. Kukreti S, Faraj A, Miles JN. Does position of syndesmotic screw affect functional and radiological outcome in ankle fractures? Injury 2005;36(9):1121–4. 10. McBryde A, Chiasson B, Wilhelm A, et al. Syndesmotic screw placement: a biomechanical analysis. Foot Ankle Int 1997;18(5):262–6. 11. Miller RS, Weinhold PS, Dahners LE. Comparison of tricortical screw fixation versus a modified suture construct for fixation of ankle syndesmosis injury: a biomechanical study. J Orthop Trauma 1999;13(1):39–42. 12. Mizel MS. Technique tip: a revised method of the Cotton test for intra-operative evaluation of syndesmotic injuries. Foot Ankle Int 2003;24(1):86–7. 13. Monga P, Kumar A, Simons A, Panikker V. Management of distal tibio-fibular syndesmotic injuries: a snapshot of current practice. Acta Orthop Belg 2008; 74(3):365–9. 14. Moore Jr JA, Shank JR, Morgan SJ, Smith WR. Syndesmosis fixation: a comparison of three and four cortices of screw fixation without hardware removal. Foot Ankle Int 2006;27(8):567–72. 15. Needleman RL, Skrade DA, Stiehl JB. Effect of the syndesmotic screw on ankle motion. Foot Ankle 1989;10(1):17–24. 16. Pneumaticos SG, Noble PC, Chatziioannou SN, Trevino SG. The effects of rotation on radiographic evaluation of the tibiofibular syndesmosis. Foot Ankle Int 2002;23(2):107–11. 17. Ramsey PL, Hamilton W. Changes in tibiotalar area of contact caused by lateral talar shift. J Bone Joint Surg Am 1976;58(3):356–7. 18. Rasmussen O. Stability of the ankle joint. Analysis of the function and traumatology of the ankle ligaments. Acta Orthop Scand Suppl 1985;211:1–75. 19. Verbrugge J. L’oste´otomie et le retournement temporaires du pe´rone´ dans la voie d’abord du cou-de-pied. Acta Orthop Belg 1949;5:195–8.