Radiologic and gross anatomic evaluation of bone healing in the dog.

Bone healing associated with 3 techniques of midshaft femoral fracture fixation in 36 young adult Beagle-type dogs was evaluated in radiographic and gross pathoanatomic studies. A serrated transverse fracture was surgically and aseptically created on the midshaft of either the left or the right femur of each dog. The fixation devices used were intramedullary (IM) pin, IM pin and 1/2 Kirschner device, and tension bone plates. The radiographic evaluation was done in series. The first radiographs were taken during surgery. Radiographs were then taken immediately after surgery, to record the status of reduction, alignment, and fixation. Radiographs were taken at the 4th and 10th postoperative weeks, to monitor healing. All dogs were euthanatized at the 10th week. Both the normal femur and the healing femur were removed from all dogs, all soft tissue was removed from the bone, and each femur was examined grossly. Each type of fixation was associated with a distinct mode of osteogenesis. Bony union and clinical union (that stage in the healing process when fixation can be removed) were defined as a successful conclusion to each case. Malunion and nonunion were defined as unsuccessful conclusions. Delayed union was defined as neither successful nor unsuccessful. The IM pin cases had a 64.2% success rate and a 14.2% failure rate. The IM pin and 1/2 Kirschner cases had a 100% success rate. The bone plate cases were 91% successful, with 0% failure. A problem identified with IM pinning was axial rotation (6 of 14 or 42% of the cases). It was concluded that IM pins should not be used alone for the fixation of femoral fractures in adult dogs.     

Metacarpal and metatarsal fractures in dogs

Metacarpal fractures were more common than metatarsal fractures in this retrospective study of 37 dogs. Fractures of one metacarpal or metatarsal bone occurred In 24 per cent of the dogs, two metacarpal bones in 16 per cent, three metacarpal or metatarsal bones in 19 per cent, and four metacarpal or metatarsal bones in 41 per cent. Eighty-seven per cent of the dogs with fractures of four bones had fracture displacement or malalignment of at least one digit. Progressive fracture healing usually occurred Irrespective of stabilisation method. For malaligned fractures, however, external coaptation did not consistently improve alignment. Fracture alignment was consistently Improved by open reduction and internal fixation of acute fractures with bone plates. Fractures of four bones occurred most often In the distal metacarpus as opposed to the proximal metatarsus. Therefore, open reduction and internal fixation may be more commonly indicated for severe metacarpal fractures, because fracture displacement or axial1 malalignment was significantly associated with fractures of the mid or distal regions of the metacarpus or metatarsus (P=0.052).     

Management of fractures of the long bones of eight cats using external skeletal fixation and a tied-in intra-medullary pin with a resin-acrylic bar

CASE HISTORY AND CLINICAL FINDINGS: Eight feline patients with fractures of the femur, tibia or humerus were presented non-weight-bearing, with varying degrees of soft tissue and concurrent injury. Five fractures were comminuted, two were open fractures and there was one malunion. TREATMENT: Fracture repair was performed in each case using a low-cost resin-acrylic external skeletal fixator (ESF). An open, limited open, or 'open but do not touch' (OBDNT) approach allowed intra-medullary (IM) pinning of the major fragments, establishing axial alignment and countering bending stress. Application of a unilateral, uniplanar (Type IA) ESF using small diameter half-pins provided stabilisation against rotational and compressive forces. The half-pins and IM pin (tied-in) were incorporated into a composite bar with the resin-acrylic. The single humeral construct incorporated a transcondylar pin into a Type I-II design. RESULTS: Seven cats, including all five comminuted fractures, had uncomplicated fracture healing. Median time to complete removal of the construct was 7 (range 5-12) weeks. In the eighth cat, an open fracture developed into a non-union, which required revision with a plate and bone graft. This cat and six others available for follow-up (median 6 months) were reported by their owners to enjoy normal activity. Two had a mild, intermittent lameness, one had a mild but persistent lameness, and four were sound. Six out of seven owners rated the appearance of their pet's limb as normal. CLINICAL RELEVANCE: The resin-acrylic ESF/tied-in IM pin construct was versatile and lightweight and allowed even highly comminuted non-load-sharing fracture configurations to be stabilised successfully using a biological strategy. Failure of the pin/acrylic interface did not occur and the frames provided sufficient strength as evidenced by healing without failure of the bar in these cases. A resin-acrylic ESF construct is inexpensive and affords the occasional orthopaedist the means to provide rotational stability when IM pinning has been used as the primary mode of fracture repair for short-oblique and transverse fractures. An extensive and costly clamp/bar inventory is not required, and there is greater flexibility for the orientation and placement of fixation pins than allowed by traditional linear bar systems.     

Comminuted long bone fractures in cats caused by pneumatic gun shot and repaired using the external fixator "tie-in" technique

Five cats with femoral fractures caused by pneumatic gun shot wounds were treated using intramedullary pin/external skeletal fixation "tie-in" (IM/ESF tie-in) technique between 1997 and 2005. Clinical and radiographical examinations were used to assess bone healing, limb function recovery and complications. Clinical results as well as fracture healing were excellent in all five cats. The study showed that the IM/ESF tie-in technique can be used in cats for the treatment of comminuted femoral fractures caused by pneumatic bullets.     

Determinants of bone mass,density and growth in growing dogs with normal and osteopenic bones

Survey radiographs of all the growing dogs aged up to 6 months, which were presented to the IVRI polyclinics during the 10 year period were screened to study the determinants of bone mass, density and growth. On the basis of clinical history and radiographic evaluation of long bones, the cases were categorized as normal or osteopenic. The relative cortical density (RCD), cortical index (CI), diameter of bone at the distal metaphysis (DDFM) and the width of the growth plate (WFGP) were determined by taking the femur as a model bone in German shepherd, Doberman and Spitz breeds of dogs at different age groups. The results showed that the RCD was the least in 0–2 month old normal growing dogs in all the breeds. As the age advanced up to 6 months the RCD increased 20–25%, and at 6 months, Spitz and Doberman showed significant increase (P < 0.05) in the RCD. In osteopenic bones, RCD remained less (25–50%) than that of normal animals at all age groups, and at 2–6 months of age, RCD in osteopenic bones was significantly lesser than in normal animals in GSD and Spitz breeds. The CI was also the least at 0–2 months of age in normal dogs. The CI increased about 50% at 4–6 months of age in GSD and Spitz. Whereas in Dob., there was no appreciable change in the CI at different age groups, and at 2–6 months it was significantly (P < 0.05) lesser than that of Spitz. In osteopenic bones, the CI was 25–75% lesser than that of normal animals at different age groups, and at 4–6 months there was significant difference (P < 0.05) between the normal and osteopenic bones in GSD and Spitz. The DDFM was the least in 0–2 month old normal growing dogs, and as the age advanced, it increased 10–20% up to 6 months. However, no significant difference in the DDFM was seen between breeds and also between the normal and osteopenic bones at different age groups. In normal animals, the WFGP was highest in the early age, subsequently it reduced 50–75% and at 4–6 months there was significant decrease (P < 0.05) in all the breeds of dogs. And at 4–6 months, there was significant (P < 0.05) difference in the WFGP between breeds, it was the least in Spitz and maximum in Dob., suggesting faster growth plate closure in Spitz than in GSD and Dob. breeds. In osteopenic bones, WFGP was generally more than in normal animals, and at 4–6 months (about 3–5 times more) there was significant difference (P < 0.05) between the normal and osteopenic bones in all breeds, indicating that physeal closure may be delayed in osteopenic bones. The results indicate that among different breeds Doberman breed has the least bone mass and may be more prone to osteopenia; whereas Spitz has the strongest bone.     

Treatment of severely comminuted diaphyseal fractures in the dog, using standard bone plates and autogenous cancellous bone graft to span fracture gaps: 11 cases (1979-1983)

Severely comminuted diaphyseal fractures in 11 dogs were repaired with standard bone plates that spanned a fracture gap filled with autogenous cancellous bone graft. Five dogs had closed injuries, 4 dogs had open fractures, and 2 dogs had infected nonunion fractures for which previous attempts at internal pin fixation had failed. A second autogenous cancellous bone graft was performed in 3 of the dogs during the healing period. The technique was successful in all dogs. The technique was considered a versatile and relatively simple alternative, compared with meticulous small fragment reconstruction and cortical bone allografts.     

Thoracic wall and pulmonary trauma in dogs sustaining fractures as a result of motor vehicle accidents

The records of 267 dogs seen at the University of Minnesota Veterinary Teaching Hospital for fractures resulting from motor vehicle accidents were examined to determine the prevalence and types of thoracic wall and pulmonary trauma associated with such cases. Results were analyzed for type and prevalence of thoracic wall and pulmonary injury, and for the prevalence of such injury in dogs with and without extrathoracic injury, in dogs with fractures of single vs multiple bones, in dogs with single fractures of specific bones, in dogs with fractures in the cranial vs the caudal one half of the body, and in dogs with fractures ipsilateral vs contralateral to thoracic injury. The overall prevalence of thoracic wall and pulmonary trauma was 38.9%; pulmonary contusions, pneumothorax, and fractured ribs were the most common injuries. More than 1 type of thoracic wall or pulmonary injury was diagnosed in 57.7% of the cases. Of the dogs with thoracic injury, 24% also had extrathoracic injuries; 16.5% of dogs without thoracic injury had extrathoracic injuries, not including fractures. Of the dogs with fractures of 1 bone, 36.3% had thoracic injuries. Of the dogs with fractures of more than 1 bone, 42.3% had thoracic injuries. The prevalence of thoracic wall and pulmonary trauma was significantly associated with the site of the fracture (cranial vs caudal and ipsilateral vs contralateral); significant association with the specific bone fractured was also seen for some fractures.     

Radial and Tibial Fracture Repair with External Skeletal Fixation: Effects of Fracture Type, Reduction, and Complications on Healing

Twenty-eight consecutive fractures of the canine radius and tibia were treated with external skeletal fixation as the primary method of stabilization. The time of fixation removal (T1) and the time to unsupported weight-bearing (T2) were correlated with: (1) bone involved; (2) communication of the fracture with the external environment; (3) severity of the fracture; (4) proximity of the fracture to the nutrient artery; (5) method of reduction; (6) diaphyseal displacement after reduction; and (7) gap between cortical fragments after reduction. The Kruskal-Wallis one-way analysis of variance was used to test the correlation with p less than .05 set as the criterion for significance. The median T1 was 10 weeks and the median T2 was 11 weeks. None of the variables correlated significantly with either of the healing times; however, there was a strong trend toward longer healing times associated with open fractures and shorter healing times associated with closed reduction. Periosteal and endosteal callus uniting the fragments were observed radiographically in comminuted fractures, with primary bone union observed in six fractures in which anatomic reduction was achieved. Complications observed in the treatment of these fractures included: bone lysis around pins (27 fractures), pin track drainage (27 fractures), pin track hemorrhage (1 fracture), periosteal reaction around pins (27 fractures), radiographic signs consistent with osteomyelitis (12 fractures), degenerative joint disease (2 dogs), and nonunion (1 fracture). Valgus or rotational malalignment resulted in 16 malunions of fractures. One external fixation device was replaced and four loose pins were removed before the fractures healed. One dog was treated with antibiotics during the postoperative period because clinical signs of osteomyelitis appeared.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ex Vivo Biomechanical Comparison of Pin Fixation Techniques for Canine Distal Femoral Physeal Fractures

Objective— To compare the biomechanical properties of five intramedullary (IM) pin fixation techniques for Salter-Harris type I fractures of the distal femur in dogs.
Study Design— Randomized, one-way factorial design composed of five treatment groups: (1) single IM pin, (2) dynamic IM crossed pins, (3) paired convergent pins, (4) crossed pins, and (5) crossed polyglycolic acid (PGA) rods.
Sample Population— Forty pairs of cadaver canine femurs.
Materials— One femur of each pair was manually fractured and subsequently repaired; the contralateral intact femur served as its control. Each femur was loaded in torsion until failure occurred and load-deformation curves were generated.
Results— The crossed-pin technique sustained the greatest load to failure (116.8%) followed by the paired convergent pins (104.8%), dynamic IM pins (90.6%), single IM pin (72.1%), and crossed PGA rods (71.9%). Statistically significant differences in strength at failure were detected between the crossed-pin and single IM pin and the crossed-pin and crossed PGA rod techniques. All fixation techniques underwent greater deformation (1.5 times as much) and had a lower stiffness (66% to 75%) compared with the intact controls; however, there was no significant difference between techniques. Failure in the paired convergent and crossed-pin techniques occurred by fracture of the bone; failure in the other techniques occurred by distraction at the fracture site.
Conclusion— The rotational stability of any of the fixation techniques appears to be primarily determined by the ability to prevent distraction and maintain interdigitation of the physis.
Clinical Relevance— When choosing a particular fixation technique for repair of a distal femoral physeal fracture, consideration should be given to the technique's relative biomechanical merits.     

Use of intramedullary fully-threaded pins in the fixation of feline and canine humeral, femoral and tibial fractures

Intramedullary fully-threaded pins were manufactured from an alloy of titanium, aluminium and vanadium in a fully-threaded style. Pins were produced in various diameters, ranging from 4 mm to 11 mm. Pin lengths varied from 5 cm to 22 cm. The proximal end of the pins was designed to fit into a hexagonal screwdriver, while the distal end was slightly tapered to allow for ease of entry into cancellous bone. Treatment using the fully-threaded intra- medullary pin was carried out in a total of 175 fractures of the humerus, femur, and tibia in 95 cats (bilateral femur in 1 case) and 77 dogs (bilateral femur in 2 cases). Radiographic follow-up for the cases was performed at monthly intervals. Non-union developed in one dog with a femoral fracture in which cerclage wire had also been used. Delayed healing and lameness were observed in two other dogs. Healing with excessive callus formation was observed in 16 dogs. However, there were not any problems noted in these dogs in regards to limb usage. Clinical and radiological results obtained for the remaining cases were found to be very good. Normal, complete fracture healing occurred between four to 14 weeks in dogs, and between four to 12 weeks in cats. Pins were removed upon observation of satisfactory functional and radiographic recovery. Pins could not be removed from 26 cats and 21 dogs as the owners had declined pin removal, or because the owners were lost to follow-up.     

Oral fractures in dogs of Brazil--a retrospective study

A retrospective study was performed in 100 dogs with 121 mandibular and 21 maxillary fractures. Dog fight (43.0%) and automobile (12.0%) trauma were the most common etiologies for fracture. The cause of fracture was unknown in 23.0% of the cases, while pathologic fractures occurred in 13.0% of cases. Young dogs (< 1-year-old) and dogs > 8-years of age were most affected. Mandibular fractures occurred in 90 dogs (90.0%), with two dogs (2.2%) having concurrent maxillary fractures. Maxillary fractures only were diagnosed in 10 dogs (10.0%). The molar region (47.1%) was the most commonly affected location for mandibular fracture, followed by fractures of the symphysis and parasymphysis (30.6%), premolar region (17.4%), angular process (4.1%) and vertical ramus (0.8%). In fractures of the mandibular region, the mandibular first molar tooth was often (85.9%) involved while the canine teeth were involved in 67.5% of symphyseal and parasymphyseal fractures. The most common fracture of the maxilla was the maxillary bone (52.4%), followed by the incisive (33.3%), palatine (9.5%), and nasal (4.8%) bones.     

Fracture healing after stabilization with intramedullary xenograft cortical bone pins: a study in pigeons

OBJECTIVE: To investigate the effectiveness of intramedullary xenograft cortical bone pins compared with stainless steel Kirschner wire for the repair of a standardized avian humeral fracture. STUDY DESIGN: Prospective randomized study. SAMPLE POPULATION: Thirty mature pigeons (Columba livia). METHODS: Birds were randomly assigned to 3 groups. Transverse mid-diaphyseal humeral fractures were created in 1 humerus in each bird. Fractures were stabilized with intramedullary ostrich or canine xenograft cortical bone pins or Kirschner wire. Radiographic, histological, and biomechanical assessments were used to compare fracture healing 6 weeks after fracture stabilization. The contralateral humerus of each bird was used as a control. RESULTS: All fractures healed regardless of intramedullary pin type. There were no statistically significant biomechanical differences among groups or within groups. Xenograft cortical bone pins induced a mononuclear inflammatory reaction that did not impair bone healing. Bones stabilized with intramedullary cortical bone pins had more periosteal callus and inflammation at the fracture site than bones stabilized with stainless steel Kirschner wires. CONCLUSIONS: Intramedullary xenograft cortical bone pins, derived from mammalian or avian sources, appear to represent an alternative for the repair of avian humeral fractures. CLINICAL RELEVANCE: Intramedullary xenograft cortical bone pins are biodegradable and may reduce the need for additional surgery to remove implants after fracture healing.     

Metacarpal fractures associated with pancarpal arthrodesis in dogs

OBJECTIVE: To report the prevalence of third metacarpal bone fractures after dorsal plating for pancarpal arthrodeses in dogs and to identify predisposing factors. STUDY DESIGN: Retrospective clinical study. ANIMALS: Fifty-four client-owned dogs. METHODS: Pancarpal arthrodesis was performed using dorsally applied 2.7- or 3.5-mm bone plates. Medical records and radiographs were retrospectively evaluated to identify those dogs with metacarpal bone fractures after pancarpal arthrodesis and to determine the angle of arthrodesis, the percentage of the third metacarpal bone covered by the bone plate, and the percentage width of the bone occupied by the screw. Radiological evidence of arthrodesis at follow-up examination 6 weeks postoperatively was recorded. Long-term results were obtained by telephone follow-up with the owners. All lame dogs were evaluated clinically and radiographically. RESULTS: Metacarpal fractures occurred in 6 of 54 dogs. One of these dogs had a stress fracture of the third metacarpal 10 months after implant removal and was not included in the statistical analysis. Fractures occurred through the distal screw hole in four dogs and involved two metacarpal bones (III and IV) in two dogs. The median ratio of bone screw diameter-to-metacarpal bone diameter was the same for dogs with metacarpal bone fractures and those with no fractures (44%), and the median angles of arthrodesis were 8 degrees and 7 degrees. These values were not statistically significant. The percentage length of the metacarpal bone covered by the plate was 53% (no fracture) compared with 46% (fracture), and this difference was statistically significant (P = .035). CONCLUSIONS: Screw diameter was not implicated as a predisposing factor for metacarpal bone fracture in dogs undergoing pancarpal arthrodesis using a dorsally applied dynamic compression plate. The length of the metacarpal bone covered by the bone plate did affect the frequency of metacarpal fracture, with fewer fractures occurring when greater than 53% of the bone length was covered by the dynamic compression plate. CLINICAL RELEVANCE: When performing pancarpal arthrodesis with a dorsally applied bone plate, it is recommended that at least 50% of the length of the third metacarpal bone should be covered by the plate.     

Clinical Use of Recombinant Human Bone Morphogenic Protein-2 in a Whooping Crane (Grus americana)

Objective— To report use of recombinant human bone morphogenetic protein-2 (rhBMP-2) as adjunctive therapy for treatment of a comminuted, open, proximal humeral fracture in an avian species.
Study Design— Clinical report.
Animals— A 3.5-month-old male whooping crane ( Grus americana ).
Methods— An open, severely comminuted humeral facture was stabilized with an intramuscular (IM) pin/type IA external skeletal fixator with tie-in configuration. rhBMP-2 was applied in a calcium phosphate matrix (CPM) paste directly to the fracture site as a bone graft substitute. Radiographic evidence of bone healing was monitored for 14 weeks.
Results— Substantial bony callus was evident at 4 weeks and at 8 weeks there was bridging callus with obvious bony remodeling. The fixation was destabilized at 9 weeks by IM pin removal, bone healing progressed and the fixator was removed at 11 weeks. By 14 weeks both cortices had been re-established with continued callus remodeling evident.
Conclusion— rhBMP-2, applied in a CPM paste, was used as a bone graft substitute in the treatment of a comminuted, open humeral fracture in a whooping crane.
Clinical Relevance— Use of rhBMP-2/CPM should be considered in treatment of avian fractures.     

Evaluation of full cortical allografts in 25 dogs

Twenty-five dogs received 26 cortical allografts from Apr 9, 1976 through Jan 31, 1982. Cortical allografts were used to reconstruct fractures of the femur, humerus, tibia, radius, and ulna. These grafts were used to replace comminuted fragments; to lengthen bones; to correct malunions, delayed unions, and nonunions; and in one case, to replace bone lost to sequestrum formation in an infected fracture site. All fractures were stabilized by use of standard ASIF techniques and dynamic compression plates. Frozen bone allografts were used in all cases. These were harvested aseptically and stored in a household freezer for 3 days to one year before use. Clinically normal function was achieved in 96% of the dogs.     

Recombinant human bone morphogenetic protein-2 in absorbable collagen sponge enhances bone healing of tibial osteotomies in dogs

OBJECTIVE: To compare the efficacy of 2 doses of recombinant human bone morphogenetic protein-2 (rhBMP-2) on tibial osteotomy healing in dogs. STUDY DESIGN: Experimental, randomized complete block (n=7). ANIMALS: Adult female dogs (n=21). METHODS: Right midshaft tibial osteotomies were created and stabilized with a 1-mm gap using type I external fixators. Seven dogs were untreated controls and 14 with osteotomies were treated with either 0.05 or 0.2 mg/mL rhBMP-2 delivered in an absorbable collagen sponge (ACS). At 8 weeks, dogs were euthanatized and bones were mechanically tested and examined by microscopy. RESULTS: Bone healing based on radiographic scoring, was significantly improved in dogs treated with 0.2 mg/mL of rhBMP-2 compared with the other groups; these tibiae were also significantly stronger and stiffer than 0.05 mg/mL rhBMP-2 and control osteotomized tibiae. Histologic scores were significantly better for 0.2 mg/mL rhBMP-2 group than 0.05 mg/mL rhBMP-2 group, but neither was significantly different from control. CONCLUSIONS: rhBMP-2 in ACS at a concentration of 0.2 mg/mL improves healing of tibial osteotomies in dogs compared with untreated controls and 0.05 mg/mL rhBMP-2 based on force plate analysis and radiographic evaluation. This was not confirmed histologically but treated bones had improved mechanical properties at 8 weeks. CLINICAL RELEVANCE: After a long bone fracture, dogs may face a long recovery period before full return of limb function. rhBMP-2, in association with good fracture fixation principles, may enhance bone healing in dogs with diaphyseal fractures.     

Prospective evaluation of minimally invasive plate osteosynthesis in 36 nonarticular tibial fractures in dogs and cats

Objective: To evaluate the clinical outcome of minimally invasive plate osteosynthesis (MIPO) for nonarticular tibial fractures stabilized using bone plates with or without an intramedullary rod (IMR). Study Design: Prospective study. Animals: Dogs (n=28) and 8 cats. Methods: After closed reduction, fracture fixation was achieved using an epiperiosteal plate inserted percutaneously through epiphyseal small incisions. In some fractures, an IMR was inserted via medial parapatellar arthrotomy. Radiographs were recommended every 3 weeks until clinical union. Postoperative tibial length and alignment were compared with contralateral measurements (P<.05). Time to clinical union and complications were recorded. Results: An IMR was used in 30.5% of the cases. Repaired tibiae were 1% shorter than contralateral tibiae (P<.05). Frontal and sagittal alignment were similar between repaired and contralateral tibiae (P>.05). Six dogs were lost for follow‐up; owners indicated normal function. In 30 cases for which bone healing was documented, mean±SD healing time was 45±20.8 days; however, when considering the 23 cases, which completed preestablished scheduled follow‐ups, healing time was 36±11.6 days. Minor complications occurred in 4 cases (11%). One major complication (3%) consisting of a plate fracture was successfully revised using MIPO with a larger plate. Conclusions: Consistent restoration of alignment was accomplished using MIPO techniques. Furthermore, MIPO appeared to yield faster healing times and lower complication rates than those reported with conventional plate osteosynthesis.     

Evaluation of transfixation casting for treatment of third metacarpal, third metatarsal, and phalangeal fractures in horses: 37 cases (1994-2004)

OBJECTIVE: To evaluate clinical findings, complications, and outcome of horses and foals with third metacarpal, third metatarsal, or phalangeal fractures that were treated with transfixation casting. DESIGN: Retrospective case series. Animals-29 adult horses and 8 foals with fractures of the third metacarpal or metatarsal bone or the proximal or middle phalanx. PROCEDURES: Medical records were reviewed, and follow-up information was obtained. Data were analyzed by use of logistic regression models for survival, fracture healing, return to intended use, pin loosening, pin hole lysis, and complications associated with pins. RESULTS: In 27 of 35 (77%) horses, the fracture healed and the horse survived, including 10 of 15 third metacarpal or metatarsal bone fractures, 11 of 12 proximal phalanx fractures, and 6 of 8 middle phalanx fractures. Four adult horses sustained a fracture through a pin hole. One horse sustained a pathologic unicortical fracture secondary to a pin hole infec-tion. Increasing body weight, fracture involving 2 joints, nondiaphyseal fracture location, and increasing duration until radiographic union were associated with horses not returning to their intended use. After adjusting for body weight, pin loosening was associated with di-aphyseal pin location, pin hole lysis was associated with number of days with a transfixation cast, and pin complications were associated with hand insertion of pins. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that transfixation casting can be successful in managing fractures distal to the carpus or tarsus in horses. This technique is most suitable for comminuted fractures of the proximal phalanx but can be used for third metacarpal, third metatarsal, or middle phalanx fractures, with or without internal fixation.     

Treatment of fractured antebrachial bones in both thoracic extremities in toy breed dogs by application of reconstruction plates

Stabilization of fractures at distal third of antebrachial bones in toy breed dogs is often connected with bone healing complications, including delayed union or non-union. In the present study 9 toy breed dogs with fractures at distal third of the epiphysis of two antebrachial bones were treated. Each dog had fractured both thoracic limbs. In all the dogs, internal stabilization was applied using the 1 mm, 4 or 5 -hole reconstructive mini plates. In three dogs mini plates were applied in treatment of non-union of antebrachial bones. In each case radius bone was stabilized only. X-ray examination performed in all the dogs 10 weeks postoperatively showed complete adhesion of treated bones. It was found that application of reconstructive mini plates in treatment of simultaneous fractures of distal shaft of both antebrachial bones is effective therapeutic method.     

Internal Skeletal Fixation Using a Kirschner Apparatus for Stabilization of Fracture/Luxations of the Lumbosacral Joint in Six Dogs: A Modification of the Transilial Pin Technique

A technique using a modification of the transilial pin technique for stabilization of fracture/ luxations of the lumbosacral joint was performed in six dogs. This technique used an internal skeletal fixator composed of two transilial pins secured with two double fixator clamps. Collapse (shortening) of the seventh lumbar vertebra (L7) was observed in five dogs without compromise of the vertebral canal. Kirschner wires placed across the articular facets as supplemental fixation devices migrated to the subcutaneous tissues in two dogs and were easily removed. Migration of the internal fixators was not observed during healing; vertebral canal dimensions were maintained in all cases, and the internal fixators were not removed after resolution of fracture healing. All fractures were healed within 6 to 12 weeks of surgery without evidence of pain, neurologic impairment, or long-term complications.