Use of meynard clamps external skeletal fixator withintramedullary tie-in pin for .in: proceedings of the 15th annual european society of veterinary orthopaedics and traumatology (esvot) congress - bologna, italy - 2010

Reprinted in the IVIS website with the permission of ESVOT 06B) posterOK_05) poster 02/09/10 12.31 Pagina 644 Reprinted in IVIS with the permission of ESVOT M. Boghossian
WVOC 2010, Bologna (Italy), 15th - 18th September • 644 Use of meynard clamps external skeletal fixator with
intramedullary tie-in pin for the treatment of femoral
fractures in dogs and cats. A four case report
M. Boghossian, DVM, MSc, V. Boghossian, DVMClínica Veterinária Penedo, Itatiaia - Rio de Janeiro, Brazil INTRODUCTION
Femur fractures commonly occur in cats and dogs and usually after substantial trauma as a result of vehic-
ular accidents. Most femur fractures are closed because of the heavy overlying muscle, unless it is a pene-
trating injury such as a gunshot wound (Beale, 2001). An intramedullary pin external skeletal fixator “tie-
in” configuration can be used in tibial, femoral and humeral fractures. In vitro testing of the configuration
using cadaver bones, more resistance to bending was gained by the tie-in arrangement than was possible
with one not tied-in, in the same work on clinical cases, no migration of the IM pin has been observed in
24 dogs and 17 cats (Aron et al. 1991). Although the meynard clamps are slightly bigger and weights more
than other clamps, some may find it easier to use because of its simple design. The design allows the appli-
cation of additional clamps to an existing frame between installed clamps without disassembling the con-
struct (Gilley et al. 2001). The purpose of the present study is to report the outcomes of the intramedular
(IM) pin external skeletal fixator “tie-in” with meynard clamps for the treatment of femoral fractures in two
dogs and two cats.
MATERIALS AND METHODS
Two dogs and two cats that had been admitted to the ‘Clínica Veterinária Penedo’ with closed fractures of
femur were enrolled in this study. The fractures were due to motor vehicle accidents (n=1) and unknown
cause (n=3). Patients were aged four months to two years and weighed 3,5 to 9,0 Kg. All the animals were
admitted with unilateral femoral fractures. Besides a femur fracture, one dog (case #2) had contralateral tib-
ial fracture, diaphragmatic hernia and sacroiliac fracture-luxation and other dog (case #4) had contralateral
second metarcarpian fracture.
After premedication with acepromazine (0,1 mg/Kg IM) and tramadol (1,0 mg/Kg IM), general anaesthesia
was induced in dogs with propofol (5 mg/Kg IV) and in cats with tiletamina (2,5 mg/kg IM) and zolazepan
(2,5 mg/Kg IM) in the same syringe, both maintained with isoflurane. In addition, epidural anaesthesia was
performed with 2% lidocaine between L7-S1 in dogs and S3-C1 in cats (1 ml per 4,5 kg). All patients were
prepared for aseptic surgery. Following the traditional approach to the bones (Piermattei et al. 2004), the
fractures were reduced and stabilized using an IM pin inserted in a retrograde fashion left protruding from
the skin proximally. Small separate incisions were made in the lateral femoral skin area through which the
external skeletal fixator (ESF) pins were inserted into the bone by slow speed drill placement. In three of the
four cases one ESF pin proximal and one distal were used and in one case two ESF pin proximal and one
distal were used. The ESF pins and IM pin were fixed with meynard clamps in a tie in fashion.
Cephalexin (30 mg/Kg, PO, q12h) was administered on the day of the surgery and for 7 days postopera-
tively. Meloxican (0,1 mg/kg, PO, q24 h) was administered on the day of surgery and for 5 days postoper-
atively.
Postoperative evaluation included, pin/skin interface, visual gait examination and time of bone healing. Ra-
diographic examinations were taken immediately after the surgical procedure and along the bone healing
period. The ESF with IM pin tie in was removed once the bone had healed. The limb functional results
were classified as ‘excellent’ (normal function of the limb); ‘good’, (functional use of the limb but partial
weight-bearing after exercise); ‘fair’ (full weight-bearing when standing, light to moderate lameness whenwalking slowly, but no weight-bearing running);‘poor’ (non-use). RESULTS
Case #1 was a cat, male, crossbreed, two years old and 3.8 kg. It was a left distal third of the diaphysis frac-
ture, presence of one small bone fragment and closed. Without other injuries. Five days after surgery the
limb function was good. The time of bone healing was 48 days, with excellent limb function. The compli-
cation was minor IM pin tract drainage. Case #2 was a dog, female, crossbreed, 7 months old with 5,6 kg.
It was a right oblique of the middle third diaphysis fracture and closed. Other injuries were left tibial frac-
ture, diaphragmatic hernia and right sacroiliac luxation/fracture. Ten days after surgery the limb function
15th Annual European ESVOT Congress - Bologna, Italy - 2010 06B) posterOK_05) poster 02/09/10 12.31 Pagina 645 Reprinted in IVIS with the permission of ESVOT • WVOC 2010, Bologna (Italy), 15th - 18th September M. Boghossian
was fair. The time of bone healing was 43 days, with good limb function. The complication was minor IMpin tract drainage. Case #3 was a cat, male, crossbreed, one year old with 3,6 kg. It was a left middle thirddiaphysis fracture, multifragmental and closed. Twenty days after surgery the limb function was excellent.
The time of bone healing was 55 days, with excellent limb function. The complication was ESF distal pintract drainage. Case # 4 was a dog, male, crossbreed, four months old with 9 kg. It was a left middle thirddiaphysis fracture, multifragmental and closed. The time of bone healing was 21 days, with excellent limbfunction. The complication was ESF distal pin tract drainageThe main complication in all 4 cases was pin tract drainage, the problem was prominent in the protrudingIM pin where there are three gluteal muscle layer. The time of bone healing was between 21 to 55 days withaverage term of 41,75 days and the age of the animals ranged between four months to 2 years. The quickbone healing was probably due to the fact that animals were less than 2 years old in this group.
CONCLUSION
It’s simple to build an ESF with IM tie in pin frame with meynard clamps. The device is more easily re-
moved than other tecniques like plate and interlocking nail. A good resistance to bending and axial rota-
tional force can be obtained with this frame. Recovery time was short and limb function after surgery was
good to excellent. The disadvantage was pin tract drainage mainly in IM pin.
REFERENCES
Aron DN, Foutz TL, Keller WG, Brown. (1991). Experimental and clinical experience with an IM pin external skeletal
fixator tie-in configuration. Vet. Comp. Orthop Traumatol; 4: 86-94.
Beale B. (2004). Orthopedic Clinical Techniques Femur Fracture Repair. Clin Tech Small Anim Pract. 19:134-150.
Gilley RS, Bourgeault CA, Wallace LJ, Bechtold JE. (2001). A comparative mechanical study of 3 external fixator clamps.
Piermattei DL, Johnson KA. (2004). An Atlas of Surgical Approaches to the Bones and Joints of the Dog and Cat. 4th 15th Annual European ESVOT Congress - Bologna, Italy - 2010

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