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Published in: HSS Journal ® 1/2007

01-02-2007 | Original Article

The Mechanics of External Fixation

Authors: Austin T. Fragomen, MD, S. Robert Rozbruch, MD

Published in: HSS Journal ® | Issue 1/2007

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Abstract

External fixation has evolved from being used primarily as a last resort fixation method to becoming a main stream technique used to treat a myriad of bone and soft tissue pathologies. Techniques in limb reconstruction continue to advance largely as a result of the use of these external devices. A thorough understanding of the biomechanical principles of external fixation is useful for all orthopedic surgeons as most will have to occasionally mount a fixator throughout their career. In this review, various types of external fixators and their common clinical applications are described with a focus on unilateral and circular frames. The biomechanical principles that govern bony and fixator stability are reviewed as well as the recommended techniques for applying external fixators to maximize stability. Additionally, we have illustrated methods for managing patients while they are in the external frames to facilitate function and shorten treatment duration.
Literature
1.
go back to reference Behrens F (1989) General theories and principles of external fixation. Clin Orthop 241:15–23PubMed Behrens F (1989) General theories and principles of external fixation. Clin Orthop 241:15–23PubMed
2.
go back to reference Claes L, Heitemeyer U, Krischak G, et al. (1999) Fixation technique influences osteogenesis of comminuted fractures. Clin Orthop 365:221–229PubMedCrossRef Claes L, Heitemeyer U, Krischak G, et al. (1999) Fixation technique influences osteogenesis of comminuted fractures. Clin Orthop 365:221–229PubMedCrossRef
3.
go back to reference Rozbruch SR, Ilizarov S, Blyakher A (2005) Knee arthrodesis with simultaneous lengthening using the Ilizarov method. J Orthop Trauma 19:171–179PubMedCrossRef Rozbruch SR, Ilizarov S, Blyakher A (2005) Knee arthrodesis with simultaneous lengthening using the Ilizarov method. J Orthop Trauma 19:171–179PubMedCrossRef
4.
go back to reference Behrens F, Searls K (1986) External fixation of the tibia. Basic concepts and prospective evaluation. J Bone Joint Surg Br 62:246–254 Behrens F, Searls K (1986) External fixation of the tibia. Basic concepts and prospective evaluation. J Bone Joint Surg Br 62:246–254
5.
go back to reference Behrens F, Johnson WD, Koch TW, Kovacevic N (1983) Bending stiffness of unilateral and bilateral fixation frames. Clin Orthop 178:103–110PubMed Behrens F, Johnson WD, Koch TW, Kovacevic N (1983) Bending stiffness of unilateral and bilateral fixation frames. Clin Orthop 178:103–110PubMed
6.
go back to reference Gasser B, Boman B, Wyder D, et al (1990) Stiffness characteristics of the circular Ilizarov device as opposed to conventional external fixators. J Biomech Eng 112:15–21PubMed Gasser B, Boman B, Wyder D, et al (1990) Stiffness characteristics of the circular Ilizarov device as opposed to conventional external fixators. J Biomech Eng 112:15–21PubMed
7.
go back to reference Ilizarov GA (1992) The Apparatus: components and biomechanical principles of application. In: Green S (Ed) Transosseus osteosynthesis. Theoretical and clinical aspects of the regeneration and growth of tissue. Springer-Verlag Berlin, pp 63–136 Ilizarov GA (1992) The Apparatus: components and biomechanical principles of application. In: Green S (Ed) Transosseus osteosynthesis. Theoretical and clinical aspects of the regeneration and growth of tissue. Springer-Verlag Berlin, pp 63–136
8.
go back to reference Duda GN, Kassi JP, Hoffman JE, et al (2000) Mechanical behavior of Ilizarov ring fixators. Effect of frame parameters on stiffness and consequences for clinical use. Unfallchirurgie 103:839–845CrossRef Duda GN, Kassi JP, Hoffman JE, et al (2000) Mechanical behavior of Ilizarov ring fixators. Effect of frame parameters on stiffness and consequences for clinical use. Unfallchirurgie 103:839–845CrossRef
9.
go back to reference Cross AR, Lewis DD, Murphy ST, et al (2001) Effects of ring diameter and wire tension on the axial biomechanics of four-ring circular external fixator constructs. Am J Vet Res 62:1025–1030PubMedCrossRef Cross AR, Lewis DD, Murphy ST, et al (2001) Effects of ring diameter and wire tension on the axial biomechanics of four-ring circular external fixator constructs. Am J Vet Res 62:1025–1030PubMedCrossRef
10.
go back to reference Podolsky A, Chao EY (1993) Mechanical performance of Ilizarov circular external fixators in comparison with other external fixators. Clin Orthop 293:61–70PubMed Podolsky A, Chao EY (1993) Mechanical performance of Ilizarov circular external fixators in comparison with other external fixators. Clin Orthop 293:61–70PubMed
11.
go back to reference Flemming B, Paley D, Kristiansen T, et al (1989) A biomechanical analysis of the Ilizarov external fixator. Clin Orthop 241:95–105 Flemming B, Paley D, Kristiansen T, et al (1989) A biomechanical analysis of the Ilizarov external fixator. Clin Orthop 241:95–105
12.
go back to reference Sarpel Y, Gulsen M, Togrul E, et al (2005) Comparison of mechanical performance among different frame configurations of the Ilizarov external fixator: experimental study. J Trauma 58:546–552PubMedCrossRef Sarpel Y, Gulsen M, Togrul E, et al (2005) Comparison of mechanical performance among different frame configurations of the Ilizarov external fixator: experimental study. J Trauma 58:546–552PubMedCrossRef
13.
go back to reference Antoci V, Roberts CS, Antoci V Jr, et al (2005) The effect of transfixion wire number and spacing between two levels of fixation on the stiffness of proximal tibial external fixation. J Orthop Trauma 19:180–186PubMedCrossRef Antoci V, Roberts CS, Antoci V Jr, et al (2005) The effect of transfixion wire number and spacing between two levels of fixation on the stiffness of proximal tibial external fixation. J Orthop Trauma 19:180–186PubMedCrossRef
14.
go back to reference Goodship AE, Watkins PE, Rigby HS, et al (1993) The role of rigid frame stiffness in the control of fracture healing. An experimental study. J Biomech 26:1027–1035PubMedCrossRef Goodship AE, Watkins PE, Rigby HS, et al (1993) The role of rigid frame stiffness in the control of fracture healing. An experimental study. J Biomech 26:1027–1035PubMedCrossRef
15.
go back to reference Kenwright J, Richardson JB, Cunningham JL, et al (1991) Axial movement and tibial fractures. A controlled randomized trial of treatment. J Bone Joint Surg Br 73:654–659PubMed Kenwright J, Richardson JB, Cunningham JL, et al (1991) Axial movement and tibial fractures. A controlled randomized trial of treatment. J Bone Joint Surg Br 73:654–659PubMed
16.
go back to reference Paley D, Fleming B, Catagni M, et al (1990) Mechanical evaluation of external fixators used in limb lengthening. Clin Orthop 250:50–57PubMed Paley D, Fleming B, Catagni M, et al (1990) Mechanical evaluation of external fixators used in limb lengthening. Clin Orthop 250:50–57PubMed
17.
go back to reference Yang L, Nayagam S, Saleh M (2003) Stiffness characteristics and inter-fragmentary displacements with different hybrid external fixators. Clin Biomech 18:166–172CrossRef Yang L, Nayagam S, Saleh M (2003) Stiffness characteristics and inter-fragmentary displacements with different hybrid external fixators. Clin Biomech 18:166–172CrossRef
18.
go back to reference Calhoun JH, Li F, Bauford WL, et al (1992) Rigidity of half pins for the Ilizarov external fixator. Bull Hosp Jt Dis 52:21–26PubMed Calhoun JH, Li F, Bauford WL, et al (1992) Rigidity of half pins for the Ilizarov external fixator. Bull Hosp Jt Dis 52:21–26PubMed
19.
go back to reference Rozbruch SR, Helfet DL, Blyakher A (2002) Distraction of hypertrophic nonunion of tibia with deformity using Ilizarov/Taylor spatial frame. Arch Orthop Trauma Surg 122:295–298PubMedCrossRef Rozbruch SR, Helfet DL, Blyakher A (2002) Distraction of hypertrophic nonunion of tibia with deformity using Ilizarov/Taylor spatial frame. Arch Orthop Trauma Surg 122:295–298PubMedCrossRef
20.
go back to reference Rozbruch SR, Weitzman AM, Watson JT, et al (2006) Simultaneous treatment of tibial bone and soft-tissue defects with the Ilizarov method. J Orthop Trauma 20(3):194–202CrossRef Rozbruch SR, Weitzman AM, Watson JT, et al (2006) Simultaneous treatment of tibial bone and soft-tissue defects with the Ilizarov method. J Orthop Trauma 20(3):194–202CrossRef
21.
go back to reference Orbay GL, Frankel VH, Kummer FJ (1992) The effect of wire configuration on the stability of the Ilizarov external fixator. Clin Orthop 279:299–302PubMed Orbay GL, Frankel VH, Kummer FJ (1992) The effect of wire configuration on the stability of the Ilizarov external fixator. Clin Orthop 279:299–302PubMed
22.
go back to reference Calhoun JH, Ledbetter BR, Gill CA (1992) Biomechanics of the Ilizarov fixator for fracture fixation. Clin Orthop 280:15–22PubMed Calhoun JH, Ledbetter BR, Gill CA (1992) Biomechanics of the Ilizarov fixator for fracture fixation. Clin Orthop 280:15–22PubMed
23.
go back to reference Roberts CS, Antoci V, Antoci V Jr, et al (2005) The effect of transfixion wire crossing angle on the stiffness of fine wire external fixation: a biomechanical study. Injury 36(9):1107–1112PubMedCrossRef Roberts CS, Antoci V, Antoci V Jr, et al (2005) The effect of transfixion wire crossing angle on the stiffness of fine wire external fixation: a biomechanical study. Injury 36(9):1107–1112PubMedCrossRef
24.
go back to reference Ilizarov GA, Emilyanova HS, Lebedev BE, et al (1772) Some experimental studies. Mechanical characteristics of Kirsherner wires. In: Perosseus compression and distraction osteosynthesis in traumatology and orthopedics. Kurgan, pp 34–47 Ilizarov GA, Emilyanova HS, Lebedev BE, et al (1772) Some experimental studies. Mechanical characteristics of Kirsherner wires. In: Perosseus compression and distraction osteosynthesis in traumatology and orthopedics. Kurgan, pp 34–47
25.
go back to reference Caja VL, Piza G, Navarro A (2003) Hydroxyapatite coating of external fixation pins decrease axial deformity during tibial lengthening for short stature. J Bone Jt Surg Am 85:1527–1531 Caja VL, Piza G, Navarro A (2003) Hydroxyapatite coating of external fixation pins decrease axial deformity during tibial lengthening for short stature. J Bone Jt Surg Am 85:1527–1531
26.
go back to reference Moroni A, Vannini F, Mosca M, et al (2002) State of the art review: techniques to avoid pin loosening and infection in external fixation. J Orthop Trauma 16:189–195PubMedCrossRef Moroni A, Vannini F, Mosca M, et al (2002) State of the art review: techniques to avoid pin loosening and infection in external fixation. J Orthop Trauma 16:189–195PubMedCrossRef
27.
go back to reference Piza G, Caja VL, Gonzalez-Viejo MA, et al (2004) Hydroxyapatite-coated external-fixation pins. The effect on pin loosening and pin-tract infection in lengthening for short stature. J Bone Jt Surg Br 86:892–897CrossRef Piza G, Caja VL, Gonzalez-Viejo MA, et al (2004) Hydroxyapatite-coated external-fixation pins. The effect on pin loosening and pin-tract infection in lengthening for short stature. J Bone Jt Surg Br 86:892–897CrossRef
28.
go back to reference Pommer A, Muhr G, David A (2002) Hydroxyapatite-coated Schantz pins in external fixators for distraction osteogenesis: a randomized, controlled trial. J Bone Jt Surg Am 84:1162–1166CrossRef Pommer A, Muhr G, David A (2002) Hydroxyapatite-coated Schantz pins in external fixators for distraction osteogenesis: a randomized, controlled trial. J Bone Jt Surg Am 84:1162–1166CrossRef
29.
go back to reference Moroni A, Faldini C, Pegreffi F, et al (2002) Fixation strength of tapered versus bicylindrical hydroxyapatite-coated external fixation pins: an animal study. J Biomed Mater Res 63:61–64PubMedCrossRef Moroni A, Faldini C, Pegreffi F, et al (2002) Fixation strength of tapered versus bicylindrical hydroxyapatite-coated external fixation pins: an animal study. J Biomed Mater Res 63:61–64PubMedCrossRef
30.
go back to reference Sarmiento A, Schaeffer JF, Beckerman L, et al (1977) Fracture healing in rat femora as affected by functional weight-bearing. J Bone Jt Surg Am 59:369–375 Sarmiento A, Schaeffer JF, Beckerman L, et al (1977) Fracture healing in rat femora as affected by functional weight-bearing. J Bone Jt Surg Am 59:369–375
31.
go back to reference Klein P, Schell H, Streitparth F, et al (2003) The initial phase of fracture healing is specifically sensitive to mechanical conditions. J Orthop Res 21:662–669PubMedCrossRef Klein P, Schell H, Streitparth F, et al (2003) The initial phase of fracture healing is specifically sensitive to mechanical conditions. J Orthop Res 21:662–669PubMedCrossRef
32.
go back to reference Herzenberg JE, Davis JR, Paley D, et al (1994) Mechanical distraction for treatment of severe knee flexion contractures. Clin Orthop Relat Res 301:80–88PubMed Herzenberg JE, Davis JR, Paley D, et al (1994) Mechanical distraction for treatment of severe knee flexion contractures. Clin Orthop Relat Res 301:80–88PubMed
33.
go back to reference Huang SC (1996) Soft tissue contractures of the knee or ankle treated by the Ilizarov technique. High recurrence rate in 26 patients followed for 3–6 years. Acta Orthop Scand 67(5):443–449PubMedCrossRef Huang SC (1996) Soft tissue contractures of the knee or ankle treated by the Ilizarov technique. High recurrence rate in 26 patients followed for 3–6 years. Acta Orthop Scand 67(5):443–449PubMedCrossRef
34.
go back to reference Carmichael KD, Maxwell SC, Calhoun JH (2005) Recurrence rates of burn contracture ankle equines and other foot deformities in children treated with Ilizarov fixation. J Pediatric Orthop 25(4):523–528CrossRef Carmichael KD, Maxwell SC, Calhoun JH (2005) Recurrence rates of burn contracture ankle equines and other foot deformities in children treated with Ilizarov fixation. J Pediatric Orthop 25(4):523–528CrossRef
35.
go back to reference Aarnes GT, Steen H, Ludvigsen P, et al (2005) In vivo assessment of regenerate axial stiffness in distraction osteogenesis. J Orthop Res 23:494–498PubMedCrossRef Aarnes GT, Steen H, Ludvigsen P, et al (2005) In vivo assessment of regenerate axial stiffness in distraction osteogenesis. J Orthop Res 23:494–498PubMedCrossRef
Metadata
Title
The Mechanics of External Fixation
Authors
Austin T. Fragomen, MD
S. Robert Rozbruch, MD
Publication date
01-02-2007
Publisher
Springer-Verlag
Published in
HSS Journal ® / Issue 1/2007
Print ISSN: 1556-3316
Electronic ISSN: 1556-3324
DOI
https://doi.org/10.1007/s11420-006-9025-0

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