Influence of the connecting rod on the biomechanical properties of five external skeletal fixation configurations

D. G. Bronson; J. D. Ross; J. P. Toombs; R. D. Welch

doi:10.1055/s-0038-1632764

Veterinary and Comparative Orthopaedics and Traumatology, Inhaltsverzeichnis

Vet Comp Orthop Traumatol 2003; 16(02): 82-87
DOI: 10.1055/s-0038-1632764

Original Research

Schattauer GmbH

Influence of the connecting rod on the biomechanical properties of five external skeletal fixation configurations

D. G. Bronson

¹Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital, Dallas, TX, USA

,

J. D. Ross

¹Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital, Dallas, TX, USA

,

J. P. Toombs

²Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Purdue University, West Lafayette, IN, USA

,

R. D. Welch

¹Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital, Dallas, TX, USA

› Institutsangaben

Abstract

Summary

A recently developed external skeletal fixation system (SK™, IMEX Veterinary, Inc.) utilizes larger diameter connecting rods, therefore overcoming one of the weaknesses of the original Kirschner-Ehmer (KE) system. The purpose of the current study was to compare five typical external fixator constructs in axial compression, torsion, Cranial-Caudal (C-C) and Medial-Lateral (M-L) bending to determine the effect of the larger connecting rods on frame stiffness. The results demonstrate that the larger connecting rod has a significant effect on overall frame stiffness. The use of two or more full-pins, as in the type II and III techniques nullified the contribution of the connecting rod diameter and frame stiffness was more a factor of pin size, number and orientation.

Keywords

External fixation - biomechanics - Kirschner-Ehmer - SK™ - connecting rod

Volltext

Referenzen

References
1 Aron DN, Dewey CW. Application and postoperative management of external skeletal fixators. Vet Clin North Am Small Anim Pract 1992; 22: 69-97.
2 Aron DN, Foutz TL, Keller WG, Brown J. Experimental and clinical experience with an IM pin external skeletal fixator tie-in configuration. Vet Comp Orthop Traumatol 1991; 1991: 86-94.
3 Augat P, Margevicius K, Simon J, Wolf S, Suger G, Claes L. Local tissue properties in bone healing: Influence of size and stability of the osteotomy gap. J Orthop Res 1998; 16: 475-81.
4 Behrens F, Johnson W. Unilateral external fixation methods to increase and reduce frame stiffness. Clin Orthop Rel Res 1989; 241: 48-56.
5 Behrens F, Johnson WD, Koch TW, Kovacevic N. Bending stiffness of unilateral and bilateral fixator frames. Clin Orthop Rel Res 1983; 178: 103-9.
6 Bouvy BM, Markel MD, Chelikani S, Egger EL, Piermattei DL, Vanderby R. Ex vivo biomechanics of Kirschner-Ehmer external skeltal fixation applied to canine tibiae. Vet Surg 1993; 22: 194-207.
7 Brighton CT. Principles of fracture healing. Part I: The biology of fracture repair. In: AAOS: Instructional Course Lectures. Murray John A. (eds). The C.V. Mosby Company; St. Louis: 1990: 60-82.
8 Brinker WO, Verstraete MC, Soutas-Little RW. Stiffness studies on various configurations and types of external fixators. J Am Anim Hosp Assoc 1985; 21: 801-8.
9 Brooks DB, Burstein AH, Frankel VH. The biomechanics of torsional fractures: The stress concentration effect of a drill hole. J Bone Joint Surg 1970; 52-A: 507-14.
10 Cheal EJ, Mansmann KA, DiGioia AM, Hayes WC, Perren SM. Role of interfragmentary strain in fracture healing: ovine model of a healing osteotomy. J Orthop Res 1991; 09: 131-42.
11 Claes L, Augat P, Suger G, Wilke H-J. Influence of size and stability of the osteotomy gap on the success of fracture healing. J Orthop Res 1997; 15: 577-84.
12 Cross AR, Aron DN, Budsberg SC, Foutz TL, Pearman BT, Evans MD. Validation of a finite element model of the Kirschner-Ehmer external skeletal fixation system. Am J Vet Res 2000; 60: 615-20.
13 Edgerton BC, An K-N, Morrey BF. Torsional strength reduction due to cortical defects in bone. J Orthop Res 1990; 08: 851-5.
14 Egger EL. Static strength evaluation of six external skeletal fixation configurations. Vet Surg 1983; 12: 130-6.
15 Egger EL. Complications of external fixation A - problem-oriented approach. Vet Clin North Am Small Anim Pract 1991; 21: 705-33.
16 Egger EL, Rigg DL, Blass CE, Berg RJ, Runyon CL, Wykes PM. Type I biplanar configuration of external skeletal fixation: Application technique in nine dogs and one cat. J Am Vet Med Assoc 1985; 187: 262-6.
17 Goodship AE, Kenwright J. The influence of induced micromovement upon the healing of experimental tibial fractures. J Bone Joint Surg 1985; 67 (B): 650-5.
18 Goodship AE, Watkins PE, Rigby HS, Kenwright J. The role of fixator frame stiffness in the control of fracture healing. An experimental study. J Biomech 1993; 26: 1027-35.
19 Grundnes O, Reikeras O. Effects of instability on bone healing. Femoral osteotomies studied in rats. ACTA Orthop Scand 1993; 64: 55-8.
20 Hipp JA, Edgerton BC, An K-N, Hayes WC. Structural consequences of transcortical holesin long bones loaded in torsion. J Biomech 1990; 23: 1261-8.
21 Johnson AL, Seitz SE, Smith CW, Johnson JM, Schaeffer DJ. Closed reduction and type-II external fixation of comminuted fractures of the radius and tibia in dogs: 23 cases (1990-1994). J Am Vet Med Assoc 1996; 209: 1445-8.
22 Kenwright J, Gardner T. Mechanical influences on tibial fracture healing. Clin Orthop 1998; 355S: 179-S190.
23 McBroom RJ, Cheal EJ, Hayes WC. Strength reductions from metastatic cortical defects in long bones. J Orthop Res 1988; 06: 369-78.
24 McPherron MA, Schwarz PD, Histand MB. Mechancial evaluation of half-pin (type 1) external skeletal fixation in combination with a single intramedullary pin. Vet Surg 1992; 21: 178-82.
25 Mills ML, Holland M, Cooper R. Use of a type-III trilateral external skeletal fixation device in three deer with comminuted fractures. J Am Vet Med Assoc 2-15-1996; 208: 559-61.
26 Molster A, Gjerdet NR, Raugstad TS, Hvidsten K, Alho A, Bang G. Effect of instability of experimental fracture healing. ACTA Orthop Scand 1982; 53: 521-6.
27 Molster AO, Gjerdet NR. Effects of instability on fracture healing in the rat. ACTA Orthop Scand 1984; 55: 342-6.
28 Norris JL, Kraus KH, O’Leary JP. Effect of supplemental plate on the stiffness of a type I external fixator. Vet Surg 2002; 31: 133-7.
29 Palmer RH, Hulse DA, Hyman WA, Palmer DR. Principles of bone healing and biomechanics of external skeletal fixation. Vet Clin North Am Small Anim Pract 1992; 22: 45-68.
30 Park S-H, O’Connor K, McKellop H, Sarmiento A. The influence of active shear or compressive motion on fracture-healing. J Bone Joint Surg 1998; 80 (A): 868-878.
31 Renegar WR, Leeds EB, Olds RB. The use of the Kirschner-Ehmer splint in clinical orthopedics part I. Long bone and mandibular fractures. The Comp Contin Ed 1982; 04: 381-91.
32 Terjesen T, Johnson E. Effects of fixation stiffness on fracture healing - External fixation of tibial osteotomy in the rabbit. ACTA Orthop Scand 1986; 57: 146-8.
33 Woodard PL, Self J, Calhoun J, Tencer AF, Evans EB. The effect of implant axial and torsional stiffness on fracture healing. J Orthop Trauma 1987; 01: 331-40.