- Email: [email protected]
Pins Versus Plates: The Orthopedic Dilemma
Symposium on Controversial Problems in Clinical Practice
Pins Versus Plates: The Orthopedic Dilemma K. R. Presnell, D.V.M., M.Sc.*
The basic objective with fracture management is to obtain and maintain reduction of fracture fragments in as near normal an anatomical position as possible. This will allow the bone and soft tissues to heal and thus restore function to the affected part. Every fracture is different in terms of the patient, the bone i~ured, the fracture type, and the other associated injuries. Each surgeon has different facilities to operate in, various equipment available, and his or her own specific ability and judgment. The surgical judgment of the surgeon is based upon knowledge, reasoning, conscience, respect for the patient, the desire to do no further harm, a disciplined approach, empathy, and self-evaluation. One must decide upon the course of treatment in view of the clinical examination of the patient, fracture type and location, future use of the dog, and the economics of the specific case. There is no method of fracture management that applies to all fractures - this is one area that involves application of the "art and science" of veterinary medicine. The following discussion will present some guidelines for the employment of pins and wires versus plates and screws for internal stabilization of fractures. Fractures suitable for external reduction and stabilization will not be discussed here. COSTS Let us first consider the basic equipment for the two systems, and second, the cost per patient. With today's escalating costs, this is becoming a serious consideration. Various bone forceps, retractors, and *Diplomate, American College of Veterinary Surgeons; Associate Professor, Department of Veterinary Clinical Studies, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
Veterinary Clinics of North America- Vol. 8, No.2, May 1978
213
214
K. R.
PRESNELL
basic soft tissue equipment are used for both systems and other operations, so they won't be considered here.
BASIC INTRAMEDULLARY PIN SYSTEM
Intramedullary pins Nine sizes, 1.5 to 6.3 mm (three of each size) Kirschner wires, 0. 71 to 1.6 mm (three of each size) Large pin cutter Small pin and wire cutter Craig pin remover Jacobs pin chuck ASIF or Richards wire twister Ten cerclage wires@ $1.50
$ 90.00 30.00 130.00 60.00 100.00 85.00 70.00 15.00 $580.00
PLATING SET
Bear in mind that the following costs are for the very minimum equipment necessary, and in the plating field, a great variety of equipment is available. Also, the costs listed below are taken from the 1977 price lists provided by the Synthes (ASIF) and the Richards Companies. Synthes veterinary #3 set Hand drill (much inferior to a power drill owing to wobble and inaccuracy) Richards small animal instrument set Plate and screw set Small plate set
$ 870.00 215.00 $1085.00 565.00 359.00 121.00 $1045.00
Either of these two sets plus a plate bender ($200.00) and two bending irons ($86.00) adds up to approximately $1400.00. A power drill is $1200.00 anda pneumatic pin shear is $400.00. RusH
PIN SET
A Rush pin set of four sizes and one pin of each length, plus an awl and driver for each size, total about $1000.00.
PINS VERSUS PLATES: THE ORTHOPEDIC DILEMMA
215
COMPARISONS CosT If we assume that the basic cost per patient for the workup, office call, radiographs, hematology, and chemistry is equal for both methods, the variables are equipment overhead, length of surgery, and cost of the inserted hardware or consumables. The cost of consumables per patient for intramedullary pin fixation ranges from $1.80 for a single pin in a small dog, to $12.90 for a large dog with one pin and four cerclage wires. The cost of two Rush pins varies from $22.00 for small ones, to $40.00 for two large pins. The plates and screws would range from $28.00 for a six hole cat plate, to $62.00 for a 10 hole dynamic compression plate with 10 screws. When you consider these prices, remember that they are cost prices as listed in the Synthes and Richards catalogues, and one must add a percentage for handling, plus interest on the investment. There is a very sizable difference between the cost of a large plate versus a large pin.
SURGICAL TIME
In terms of the surgical time required for application of the internal appliance, it is greater in most cases for plate application than for insertion of an intramedullary pin. The soft tissue exposure is much greater for plate application. Also, the surgical remov;:tl of most pins requires very little time and surgical preparation,. compared with removal of plates and screws.
FACTORS AFFECTING METHOD OF REPAIR A. Surgeon- basic knowledge - surgical skill and success with various methods of fixation (experience and training) -available equipment - adequate clean facilities B. Patient- size or weight -age as it affects healing time -the bone involved -other fractures
216
K. R.
PRESNELL
-other soft tissue injuries (e.g., IS it compound and contaminated?) -type of fracture -area of the bone involved C. Owner- amount of time and care that can be provided at home -the future use for the patient (e.g., showing or breeding) -value of the patient to owner
DISCUSSION The following indicates how I prefer to handle certain fractures. There are certain types of fractures that can be categorized fairly readily. Spinal luxations, fractures, or laminectomies should be stabilized with plates, the best of which appears to be plastic plates.* Fractures of the mandible, other than symphyseal, are best stabilized with plates, especially if distraction is required. Mandibular symphyseal fractures are most readily treated with wire or a Steinman pin and wire. Pelvic fractures that need stabilization are usually iliosacral separations or fractures, which only require two screws inserted on the lag principle. Fractures of the ilium lend themselves well to small four to six hole plates. Acetabular fractures are difficult to plate, but plates provide the best stability and thus the greatest chance for success. Fractures best handled with the lag screw technique are fractures of the femoral neck, the intercondylar fractures of the distal femur or humerus, and the slab fractures of the tibial plateau. Intraarticular fractures should be compressed and fixed with screws and plates. The tension band wire fixation with one or two small intramedullar pins can best be employed to treat fractures of the tuber calcis, the olecranon, the greater trochanter of the femur, the greater tubercle of the humerus, the lateral malleolus of the fibula, or the medial malleolus of the tibia. These fixations are very stable and use a minimum of consumables. This leaves the diaphysis of the long bones, which can be handled by either method. The radius can be readily pinned in a normograde manner from the distal end by inserting the pin from the cranial aspect, not passing through the articular cartilage. The ulna can be pinned from the proximal end. Pins work well for these fractures, but the shape of the medullary cavity of the radius only admits a small pin proximally, and thus added external support is needed. Plates are readily applied to the radius and provide excellent stability. A small humerus can be readily stabilized with intramedullary *Lubra Plate Company, Fort Collins, Colorado.
PINS VERSUS PLATES: THE ORTHOPEDIC DILEMMA
217
pins, and plates should be employed for medium and large size dogs. The femur is treated likewise, owing to the excessive bending forces on it. The tibia can be pinned easily in a normograde manner, starting in the stifle joint on the medial plateau at a point halfway between the meniscus and tibial crest. It also is a bone that is easy to plate. The metacarpal or metatarsal bones should be pinned or wired, but seldom, if ever, plated. Pins are employed only in fractures in which the ends are irregular enough to interdigitate in order to stop rotation, or else hemicerclage wires must be used. Comminuted fractures can be pinned and full cerclage wired if there are only one or two large pieces besides the two main fragments. If there are a number of small fragments or a defect in the bone that must be maintained in distraction, a plate and screws provide the best stability and should be used. Plates and screws provide the greatest stability and should be used for long bones in medium, large, and giant breeds of dogs. The shape of the meduilary canal of the femur, humerus, and tibia is irregular and is not a smooth cylinder; therefore, it is not easily filled with an intramedullary pin. The small to medium size dogs can be treated with either pins and wires or plates and screws, providing the proper principles and techniques are employed. Special surgical procedures, such as arthrodesis of joints (stifle, elbow, carpus, or shoulder), corrective wedge osteotomies, and full cortical bone grafts should be stabilized with plates and screws. Nonunions are best treated with plate fixation, since healing is usually much slower than normally expected, and thus stability is required for a longer period. Also, compression of the fracture site appears to aid healing of a nonunion or delayed union. Department of Veterinary Clinical Studies Western College of Veterinary Medicine University of Saskatchewan Saskatoon, Saskatchewan Canada S7N OWO
Pins Versus Plates: The Orthopedic Dilemma K. R. Presnell, D.V.M., M.Sc.*
The basic objective with fracture management is to obtain and maintain reduction of fracture fragments in as near normal an anatomical position as possible. This will allow the bone and soft tissues to heal and thus restore function to the affected part. Every fracture is different in terms of the patient, the bone i~ured, the fracture type, and the other associated injuries. Each surgeon has different facilities to operate in, various equipment available, and his or her own specific ability and judgment. The surgical judgment of the surgeon is based upon knowledge, reasoning, conscience, respect for the patient, the desire to do no further harm, a disciplined approach, empathy, and self-evaluation. One must decide upon the course of treatment in view of the clinical examination of the patient, fracture type and location, future use of the dog, and the economics of the specific case. There is no method of fracture management that applies to all fractures - this is one area that involves application of the "art and science" of veterinary medicine. The following discussion will present some guidelines for the employment of pins and wires versus plates and screws for internal stabilization of fractures. Fractures suitable for external reduction and stabilization will not be discussed here. COSTS Let us first consider the basic equipment for the two systems, and second, the cost per patient. With today's escalating costs, this is becoming a serious consideration. Various bone forceps, retractors, and *Diplomate, American College of Veterinary Surgeons; Associate Professor, Department of Veterinary Clinical Studies, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
Veterinary Clinics of North America- Vol. 8, No.2, May 1978
213
214
K. R.
PRESNELL
basic soft tissue equipment are used for both systems and other operations, so they won't be considered here.
BASIC INTRAMEDULLARY PIN SYSTEM
Intramedullary pins Nine sizes, 1.5 to 6.3 mm (three of each size) Kirschner wires, 0. 71 to 1.6 mm (three of each size) Large pin cutter Small pin and wire cutter Craig pin remover Jacobs pin chuck ASIF or Richards wire twister Ten cerclage wires@ $1.50
$ 90.00 30.00 130.00 60.00 100.00 85.00 70.00 15.00 $580.00
PLATING SET
Bear in mind that the following costs are for the very minimum equipment necessary, and in the plating field, a great variety of equipment is available. Also, the costs listed below are taken from the 1977 price lists provided by the Synthes (ASIF) and the Richards Companies. Synthes veterinary #3 set Hand drill (much inferior to a power drill owing to wobble and inaccuracy) Richards small animal instrument set Plate and screw set Small plate set
$ 870.00 215.00 $1085.00 565.00 359.00 121.00 $1045.00
Either of these two sets plus a plate bender ($200.00) and two bending irons ($86.00) adds up to approximately $1400.00. A power drill is $1200.00 anda pneumatic pin shear is $400.00. RusH
PIN SET
A Rush pin set of four sizes and one pin of each length, plus an awl and driver for each size, total about $1000.00.
PINS VERSUS PLATES: THE ORTHOPEDIC DILEMMA
215
COMPARISONS CosT If we assume that the basic cost per patient for the workup, office call, radiographs, hematology, and chemistry is equal for both methods, the variables are equipment overhead, length of surgery, and cost of the inserted hardware or consumables. The cost of consumables per patient for intramedullary pin fixation ranges from $1.80 for a single pin in a small dog, to $12.90 for a large dog with one pin and four cerclage wires. The cost of two Rush pins varies from $22.00 for small ones, to $40.00 for two large pins. The plates and screws would range from $28.00 for a six hole cat plate, to $62.00 for a 10 hole dynamic compression plate with 10 screws. When you consider these prices, remember that they are cost prices as listed in the Synthes and Richards catalogues, and one must add a percentage for handling, plus interest on the investment. There is a very sizable difference between the cost of a large plate versus a large pin.
SURGICAL TIME
In terms of the surgical time required for application of the internal appliance, it is greater in most cases for plate application than for insertion of an intramedullary pin. The soft tissue exposure is much greater for plate application. Also, the surgical remov;:tl of most pins requires very little time and surgical preparation,. compared with removal of plates and screws.
FACTORS AFFECTING METHOD OF REPAIR A. Surgeon- basic knowledge - surgical skill and success with various methods of fixation (experience and training) -available equipment - adequate clean facilities B. Patient- size or weight -age as it affects healing time -the bone involved -other fractures
216
K. R.
PRESNELL
-other soft tissue injuries (e.g., IS it compound and contaminated?) -type of fracture -area of the bone involved C. Owner- amount of time and care that can be provided at home -the future use for the patient (e.g., showing or breeding) -value of the patient to owner
DISCUSSION The following indicates how I prefer to handle certain fractures. There are certain types of fractures that can be categorized fairly readily. Spinal luxations, fractures, or laminectomies should be stabilized with plates, the best of which appears to be plastic plates.* Fractures of the mandible, other than symphyseal, are best stabilized with plates, especially if distraction is required. Mandibular symphyseal fractures are most readily treated with wire or a Steinman pin and wire. Pelvic fractures that need stabilization are usually iliosacral separations or fractures, which only require two screws inserted on the lag principle. Fractures of the ilium lend themselves well to small four to six hole plates. Acetabular fractures are difficult to plate, but plates provide the best stability and thus the greatest chance for success. Fractures best handled with the lag screw technique are fractures of the femoral neck, the intercondylar fractures of the distal femur or humerus, and the slab fractures of the tibial plateau. Intraarticular fractures should be compressed and fixed with screws and plates. The tension band wire fixation with one or two small intramedullar pins can best be employed to treat fractures of the tuber calcis, the olecranon, the greater trochanter of the femur, the greater tubercle of the humerus, the lateral malleolus of the fibula, or the medial malleolus of the tibia. These fixations are very stable and use a minimum of consumables. This leaves the diaphysis of the long bones, which can be handled by either method. The radius can be readily pinned in a normograde manner from the distal end by inserting the pin from the cranial aspect, not passing through the articular cartilage. The ulna can be pinned from the proximal end. Pins work well for these fractures, but the shape of the medullary cavity of the radius only admits a small pin proximally, and thus added external support is needed. Plates are readily applied to the radius and provide excellent stability. A small humerus can be readily stabilized with intramedullary *Lubra Plate Company, Fort Collins, Colorado.
PINS VERSUS PLATES: THE ORTHOPEDIC DILEMMA
217
pins, and plates should be employed for medium and large size dogs. The femur is treated likewise, owing to the excessive bending forces on it. The tibia can be pinned easily in a normograde manner, starting in the stifle joint on the medial plateau at a point halfway between the meniscus and tibial crest. It also is a bone that is easy to plate. The metacarpal or metatarsal bones should be pinned or wired, but seldom, if ever, plated. Pins are employed only in fractures in which the ends are irregular enough to interdigitate in order to stop rotation, or else hemicerclage wires must be used. Comminuted fractures can be pinned and full cerclage wired if there are only one or two large pieces besides the two main fragments. If there are a number of small fragments or a defect in the bone that must be maintained in distraction, a plate and screws provide the best stability and should be used. Plates and screws provide the greatest stability and should be used for long bones in medium, large, and giant breeds of dogs. The shape of the meduilary canal of the femur, humerus, and tibia is irregular and is not a smooth cylinder; therefore, it is not easily filled with an intramedullary pin. The small to medium size dogs can be treated with either pins and wires or plates and screws, providing the proper principles and techniques are employed. Special surgical procedures, such as arthrodesis of joints (stifle, elbow, carpus, or shoulder), corrective wedge osteotomies, and full cortical bone grafts should be stabilized with plates and screws. Nonunions are best treated with plate fixation, since healing is usually much slower than normally expected, and thus stability is required for a longer period. Also, compression of the fracture site appears to aid healing of a nonunion or delayed union. Department of Veterinary Clinical Studies Western College of Veterinary Medicine University of Saskatchewan Saskatoon, Saskatchewan Canada S7N OWO