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Closed intramedullary nailing complicated by breakage of plastic medullary tube
Injury: the British Journal of Accident Surgery (1993) Vol. 24/No.
136
Discussion Vascular complications associated with the use of any transfixing external fixator are usually attributed to improper pin insertion technique and imprecise familiarity with cross-sectional anatomy. In the case of the Ilizarov fixator these include perforation of artery, vein, or both (Behrens, 1989; Paley, 1990, 1991a). Transfixion pin configurations utilized by ring fixators predispose to vascular injury as the pins cannot pass through completely ‘safe corridors’ while maintaining optimal stability (Behrens, 1989). In the thigh, efforts to avoid damage to major neurovascular structures by using half-pins instead of transfixing pins, have led to the development of a ‘hybrid’ configuration. This combines the axially stiffer fixation of the Hoffman-type system proximally with the elasticity of the Ilizarov radial fixator distally. The unique biomechanical property of the Ilizarov fixator permits intermittent closure of the fracture gap. This takes place through a predominantly axial telescopic motion on loading, and is due to the large deflection of the thin wires (Chao and Aro, 1989). In the hybrid configuration, cyclic loading at the fracture gap is attributable mainly to motion of the distal construct because the proximal element is relatively rigid (Paley, 199Ib). Although a late presentation of asymptomatic arterial damage at the time of wire insertion cannot be excluded, in our patient late vascular erosion should be considered. This has previously been ascribed to pulsation of an artery against an adjacent wire (Paley, 1990, 1991b). We further propose that the axial micromovement of a transfixion wire against an arterial wall may be an aggra-
vating factor in progressive pseudoaneurysm formation.
2
arterial erosion leading to late
References Behrens F. (1989) General theory and principles of external fixation. Clin. otthop. 241, 15. Chao E. Y. S. and Aro H. T. (1989) Biomechanics and biology of external fixation. In: Coombs R., Green S., Sarmiento A. (eds) Ertemal Fixation and Functional Bracing. London, Orthotext, 83. Gallinaro P., Biasibetti A., Demangos J. et al. (1989) Non-union. In: Coombs R., Green S., Sarmiento A. (eds). External Fixafian and Ftmcfio& Bracing. London: Orthotext, 265. Paley D. (1990) Problems, obstacles, and complications of limb lengthening by the Ilizarov technique. Clin. orfhop. 250, 81. Paley D. (1991a) Problems, obstacles and complications of limb lengthening. In: Maiocchi A. B. and Anderson J. (eds). Operative Pn’nciplesof Ilizarov. Baltimore: Williams and Wilkins, 359. Paley D. (199Ib) Biomechanics of the Ilizarov external fixator. In: Maiocchi A. B. and Aronson J. (eds). Operative Principles of %zrov. Baltimore: Williams and Wilkins, 33.
Paper accepted
19 March
1992.
Requests for reprints should be addressed to: Professor
M. B. E. Sweet, University of the Witwatersrand, Medical School, 7 York Road, Parktown 2193, Johannesburg, South Africa.
Closed intramedullary nailing complicated breakage of plastic medullary tube
by
S. P. Godsiff and M. B. Heywood-Waddington Broomfield Hospital, Chelmsford,
Essex, UK
Introduction
Case reports
Closed intramedullary nailing is an accepted method of treatment for fractures of the diaphysis of the femur and tibia (Kempf et al., 1985; Christie et al., 198s; Court-Brown et al., 1990). The technique is technically demanding and requires the fracture to be reduced adequately before the medullary cavity is reamed to accept the nail. Reaming is usually accompanied by, first, passing an olive-tipped guidewire across the fracture site and then, using progressively larger cutting heads, the medullary cavity is reamed up to the desired diameter. At this stage the olive-tipped guidewire is exchanged for a smooth-tipped guidewire to allow the nail to be driven home. To prevent loss of reduction of the fracture when exchanging the guidewires, a plastic medullary tube is used over the first guidewire, through which it may be exchanged for the smooth-tipped guidewire, the plastic tube then being withdrawn. We report two cases where the plastic meddlary tube broke in the medullary cavity of the bone. Considerable difficulty was experienced in removing the fragments. 0 1993 Butterworth-Heinemann 0020-1383/93/020136-02
Ltd
Case 1
A 27-year-old man sustained an unstable short oblique fracture of the midshaft of his right tibia and it was elected to treat this by a closed intramedullary nail. After adequate reduction the medullary cavity was reamed up to 12 mm and, using a plastic sleeve, the olive-tipped guidewire was replaced by the smooth-tipped wire. On attempting to remove the plastic tube it broke some 3cm proximal to the fracture site. Attempts to remove the fragment with broken-nail extractors failed and the fracture site had to be opened in order to retrieve the segment of plastic tube. The broken tube was dirty brown in colour, and two other similarly coloured sleeves were found in the same instrument set, both of which broke on attempting to bend them. Nailing was performed in an open fashion and fortunately the patient recovered uneventfully and progressed to union. Case 2 A 33-year-old man sustained a closed transverse fracture of his right femur. During the operation to internally fix this injury with
Case reports
137
a closed intramedullav nail, a discoloured plastic medullary tube broke in the medullary cavity proximal to the fracture site as the guidewires were being exchanged. A flexible light source was passed into the medullary cavity in an attempt to visualize the broken segment and fortunately jammed in the lumen of the tube allowing it to be withdrawn. Nailing was then accomplished without further incident. One other discoloured plastic tube in the set broke on attempting to bend it.
Discussion New or little used plastic medullary
tubes are opalescent and flexible, easily touching end-to-end when flexed. With repeated autoclaving the colour of the plastic changes to a dirty brown and the tubes lose their flexibility. It has been recommended that the medullary tubes be checked regularly for flexibility (Texhamar and Sequin, 1981). We would further caution against the use of any discoloured medullary tube without first checking its flexibility and would recommend that suspect tubes be discarded.
Interlocking
References Christie J., Court-Brown C. et al. (1988)Intramedullary locking nails in the management of femoral shaft fractures. 1. Bone Joint Surg. 70B, 206. Court-Brown C. et al. (1990) Closed intramedullary tibia1 nailing.]. Bone Joint Surg 72B, 605. Kempf I. et al. (1985) Closed locked intramedullary nailing. J Bone Joint Surg. 67A, 709. Texhamar R. and Sequin F. (1981) AO/ASIF hshumntution Mmtral of Use and Care. Berlin Heidelberg: Springer-Verlag. Paper accepted
I1 May
1992.
Reqmts fur reprints should be addressed to: Mr S. P. Godsiff, Orthopaedic Registrar, Broomfield Hospital, Chelmsford, Essex CM1 5ET, UK.
screw length in intramedullary
nailing
J. F. Nolan Orthopaedic
Department,
Princess Alexandra
Hospital, Harlow, Essex, UK
Introduction
lntramedullary
Interlocking nailing is a useful addition to the armarnentarium of the trauma surgeon. Among other practical difficulties encountered during the procedure, use of the depth gauge to measure the length of interlocking screws may be hampered by inability to locate the hook of the instrument on the relevant cortex, and by surrounding soft tissues. Estimation of screw length by other methods, including radiological assessment, may be subject to parallax error and, once inserted, a screw of incorrect length may be awkward to remove, or replace. After location of the screw holes, either freehand or with a centering device, most surgeons switch from the lateral to the anteroposterior projection with the image intensifier, in order to confirm the position of the drill bit through the nail.
nail
(Driver removed)
Figure 1. Diagramatic
representation image intensifier projection.
of the anteroposterior
Method It is suggested that after penetration of the distal cortex, the drill bit is positioned so that its tip lies the required distance beyond the bone, representing the desired position of the tip of the screw. Confirmation of this, and that the drill sleeve has remained in contact with the proximal cortex is sought with the anteroposterior projection (Figure I). The drill driver is then removed, and the length of the drill bit which is exposed beyond the end of the guide is measured (b). Drill sleeve and bit are then removed from the limb by hand, and their measured relationship restored. Measurement of the uncovered drill bit beyond the bone end of the sleeve (a), is the exact length of screw required. 8
1993 Butterworth-Heinemann
0020-1383/93:020137-01
Ltd
Discussion This method has proved to be simple and reliable. It requires no equipment additional to the basic instrumentation used for interlocking nailing procedures, and common to all manufacturers’ sets. Paper accepted
11 May 1992.
Requests for reprints skouM be aaYmsed to: Mr J. F. Nolan, Norfolk and Norwich Hospital, Brunswick Road, Norwich, Norfolk NRI XSR, UK.
136
Discussion Vascular complications associated with the use of any transfixing external fixator are usually attributed to improper pin insertion technique and imprecise familiarity with cross-sectional anatomy. In the case of the Ilizarov fixator these include perforation of artery, vein, or both (Behrens, 1989; Paley, 1990, 1991a). Transfixion pin configurations utilized by ring fixators predispose to vascular injury as the pins cannot pass through completely ‘safe corridors’ while maintaining optimal stability (Behrens, 1989). In the thigh, efforts to avoid damage to major neurovascular structures by using half-pins instead of transfixing pins, have led to the development of a ‘hybrid’ configuration. This combines the axially stiffer fixation of the Hoffman-type system proximally with the elasticity of the Ilizarov radial fixator distally. The unique biomechanical property of the Ilizarov fixator permits intermittent closure of the fracture gap. This takes place through a predominantly axial telescopic motion on loading, and is due to the large deflection of the thin wires (Chao and Aro, 1989). In the hybrid configuration, cyclic loading at the fracture gap is attributable mainly to motion of the distal construct because the proximal element is relatively rigid (Paley, 199Ib). Although a late presentation of asymptomatic arterial damage at the time of wire insertion cannot be excluded, in our patient late vascular erosion should be considered. This has previously been ascribed to pulsation of an artery against an adjacent wire (Paley, 1990, 1991b). We further propose that the axial micromovement of a transfixion wire against an arterial wall may be an aggra-
vating factor in progressive pseudoaneurysm formation.
2
arterial erosion leading to late
References Behrens F. (1989) General theory and principles of external fixation. Clin. otthop. 241, 15. Chao E. Y. S. and Aro H. T. (1989) Biomechanics and biology of external fixation. In: Coombs R., Green S., Sarmiento A. (eds) Ertemal Fixation and Functional Bracing. London, Orthotext, 83. Gallinaro P., Biasibetti A., Demangos J. et al. (1989) Non-union. In: Coombs R., Green S., Sarmiento A. (eds). External Fixafian and Ftmcfio& Bracing. London: Orthotext, 265. Paley D. (1990) Problems, obstacles, and complications of limb lengthening by the Ilizarov technique. Clin. orfhop. 250, 81. Paley D. (1991a) Problems, obstacles and complications of limb lengthening. In: Maiocchi A. B. and Anderson J. (eds). Operative Pn’nciplesof Ilizarov. Baltimore: Williams and Wilkins, 359. Paley D. (199Ib) Biomechanics of the Ilizarov external fixator. In: Maiocchi A. B. and Aronson J. (eds). Operative Principles of %zrov. Baltimore: Williams and Wilkins, 33.
Paper accepted
19 March
1992.
Requests for reprints should be addressed to: Professor
M. B. E. Sweet, University of the Witwatersrand, Medical School, 7 York Road, Parktown 2193, Johannesburg, South Africa.
Closed intramedullary nailing complicated breakage of plastic medullary tube
by
S. P. Godsiff and M. B. Heywood-Waddington Broomfield Hospital, Chelmsford,
Essex, UK
Introduction
Case reports
Closed intramedullary nailing is an accepted method of treatment for fractures of the diaphysis of the femur and tibia (Kempf et al., 1985; Christie et al., 198s; Court-Brown et al., 1990). The technique is technically demanding and requires the fracture to be reduced adequately before the medullary cavity is reamed to accept the nail. Reaming is usually accompanied by, first, passing an olive-tipped guidewire across the fracture site and then, using progressively larger cutting heads, the medullary cavity is reamed up to the desired diameter. At this stage the olive-tipped guidewire is exchanged for a smooth-tipped guidewire to allow the nail to be driven home. To prevent loss of reduction of the fracture when exchanging the guidewires, a plastic medullary tube is used over the first guidewire, through which it may be exchanged for the smooth-tipped guidewire, the plastic tube then being withdrawn. We report two cases where the plastic meddlary tube broke in the medullary cavity of the bone. Considerable difficulty was experienced in removing the fragments. 0 1993 Butterworth-Heinemann 0020-1383/93/020136-02
Ltd
Case 1
A 27-year-old man sustained an unstable short oblique fracture of the midshaft of his right tibia and it was elected to treat this by a closed intramedullary nail. After adequate reduction the medullary cavity was reamed up to 12 mm and, using a plastic sleeve, the olive-tipped guidewire was replaced by the smooth-tipped wire. On attempting to remove the plastic tube it broke some 3cm proximal to the fracture site. Attempts to remove the fragment with broken-nail extractors failed and the fracture site had to be opened in order to retrieve the segment of plastic tube. The broken tube was dirty brown in colour, and two other similarly coloured sleeves were found in the same instrument set, both of which broke on attempting to bend them. Nailing was performed in an open fashion and fortunately the patient recovered uneventfully and progressed to union. Case 2 A 33-year-old man sustained a closed transverse fracture of his right femur. During the operation to internally fix this injury with
Case reports
137
a closed intramedullav nail, a discoloured plastic medullary tube broke in the medullary cavity proximal to the fracture site as the guidewires were being exchanged. A flexible light source was passed into the medullary cavity in an attempt to visualize the broken segment and fortunately jammed in the lumen of the tube allowing it to be withdrawn. Nailing was then accomplished without further incident. One other discoloured plastic tube in the set broke on attempting to bend it.
Discussion New or little used plastic medullary
tubes are opalescent and flexible, easily touching end-to-end when flexed. With repeated autoclaving the colour of the plastic changes to a dirty brown and the tubes lose their flexibility. It has been recommended that the medullary tubes be checked regularly for flexibility (Texhamar and Sequin, 1981). We would further caution against the use of any discoloured medullary tube without first checking its flexibility and would recommend that suspect tubes be discarded.
Interlocking
References Christie J., Court-Brown C. et al. (1988)Intramedullary locking nails in the management of femoral shaft fractures. 1. Bone Joint Surg. 70B, 206. Court-Brown C. et al. (1990) Closed intramedullary tibia1 nailing.]. Bone Joint Surg 72B, 605. Kempf I. et al. (1985) Closed locked intramedullary nailing. J Bone Joint Surg. 67A, 709. Texhamar R. and Sequin F. (1981) AO/ASIF hshumntution Mmtral of Use and Care. Berlin Heidelberg: Springer-Verlag. Paper accepted
I1 May
1992.
Reqmts fur reprints should be addressed to: Mr S. P. Godsiff, Orthopaedic Registrar, Broomfield Hospital, Chelmsford, Essex CM1 5ET, UK.
screw length in intramedullary
nailing
J. F. Nolan Orthopaedic
Department,
Princess Alexandra
Hospital, Harlow, Essex, UK
Introduction
lntramedullary
Interlocking nailing is a useful addition to the armarnentarium of the trauma surgeon. Among other practical difficulties encountered during the procedure, use of the depth gauge to measure the length of interlocking screws may be hampered by inability to locate the hook of the instrument on the relevant cortex, and by surrounding soft tissues. Estimation of screw length by other methods, including radiological assessment, may be subject to parallax error and, once inserted, a screw of incorrect length may be awkward to remove, or replace. After location of the screw holes, either freehand or with a centering device, most surgeons switch from the lateral to the anteroposterior projection with the image intensifier, in order to confirm the position of the drill bit through the nail.
nail
(Driver removed)
Figure 1. Diagramatic
representation image intensifier projection.
of the anteroposterior
Method It is suggested that after penetration of the distal cortex, the drill bit is positioned so that its tip lies the required distance beyond the bone, representing the desired position of the tip of the screw. Confirmation of this, and that the drill sleeve has remained in contact with the proximal cortex is sought with the anteroposterior projection (Figure I). The drill driver is then removed, and the length of the drill bit which is exposed beyond the end of the guide is measured (b). Drill sleeve and bit are then removed from the limb by hand, and their measured relationship restored. Measurement of the uncovered drill bit beyond the bone end of the sleeve (a), is the exact length of screw required. 8
1993 Butterworth-Heinemann
0020-1383/93:020137-01
Ltd
Discussion This method has proved to be simple and reliable. It requires no equipment additional to the basic instrumentation used for interlocking nailing procedures, and common to all manufacturers’ sets. Paper accepted
11 May 1992.
Requests for reprints skouM be aaYmsed to: Mr J. F. Nolan, Norfolk and Norwich Hospital, Brunswick Road, Norwich, Norfolk NRI XSR, UK.