Use of a circular fixator construct to facilitate closed reduction and percutaneous stabilization of a distal femoral physeal fracture in a dog.

Background: Fractures of the distal femoral physis are the most common physeal fracture sustained by skeletally immature dogs. Reduction and stabilization of these fractures can sometimes be achieved through closed reduction, primarily in fractures that are nominally displaced. Circular external fixator constructs have been used to assist in indirect, closed reduction of fractures at other anatomic locations in dogs and this report describes application of this method to reduce a displaced Salter-Harris type II fracture of the distal femur in a 1-year-old dog. Case Description: A 1-year-old female spayed Akita was referred for treatment of a Salter-Harris type II fracture of the right distal femur. The epiphyseal segment was laterally and slightly caudally displaced. Multiple attempts to manually reduce the fracture during surgery were unsuccessful, so a two-ring circular external fixator construct was applied to facilitate distraction and reduction. The construct was applied by placing a medial-to-lateral Kirschner wire in both the mid-femoral diaphysis and in the distal femoral epiphysis. Distraction of the construct provided sufficient separation of the fracture segments to facilitate near anatomic reduction. The fracture was stabilized with two percutaneously placed Steinmann pins placed in Rush fashion. Radiographic union was confirmed 5 weeks after surgery. The dog was not lame and was bearing more weight on the right pelvic limb, as assessed using force plate analysis, 9 months following surgery. Goniometric measurements of stifle range of motion and thigh muscle circumference were similar between the pelvic limbs. Conclusion: Application of a two-ring circular construct would appear to be useful to facilitate closed reduction and percutaneous stabilization of distal femoral physeal fractures.

SUCCESSFUL REPAIR OF ANTEBRACHIAL FRACTURES WITH EXTERNAL SKELETAL FIXATION IN THREE MACROPODS.

Three captive macropods comprising three different species sustained unilateral antebrachial fractures. All fractures were assumed to be trauma related, although the specific circumstances surrounding each case was unknown. Each fracture was surgically repaired with type Ia (unilateral, monoplanar) external skeletal fixators, which were all removed approximately 3 mo postoperatively. Although each animal experienced at least one complication, all animals showed adequate bridging and remodeling at the fracture sites and had good-to-excellent return to normal function after fixator removal. This case series is the first to describe the successful repair of antebrachial fractures using external skeletal fixation in captive macropods and details some of the complications that can occur with postoperative management of captive animals.

A simple technique to repair a hand fracture in a captive Siamang.

A 5-year-old female Siamang (Hylobates syndactilus) in captivity sustained a displaced closed fracture of the proximal phalanx of the middle digit, resulting in finger deformity and hand functional disability. Anatomical reduction and stabilization of the fracture were obtained surgically using two multifilament wire sutures. The primate had a successful functional recovery.

Successful treatment of a radioulnar synostosis in a Mississippi kite (Ictinia mississippiensis).

A Mississippi kite (Ictinia mississippiensis) was presented to the Wildlife Hospital of Louisiana, School of Veterinary Medicine, Louisiana State University, for an inability to fly and was subsequently diagnosed with a minimally displaced, closed, simple, short oblique, diaphyseal fracture of the distal third of the right ulna. A figure-8 bandage was initially applied to the wing to stabilize the fracture. Over a 5-week period, the kite developed progressive reduction in wing extension, and serial radiographs revealed a bridging callus at the ulnar fracture site, as well as development of a radioulnar synostosis. To restore wing function and extension, surgical excision of the bony union between the radius and the ulna was performed, after which a polypropylene mesh implant was interposed between the 2 bones. Within 2 weeks after the surgical procedure, the kite had recovered normal wing extension and was able to fly without noticeable impairment. The bird was released 2 weeks after surgery. This case illustrates a common complication of external coaptation used as sole means of managing fractures of the avian ulna, radius, or both, which results from lack of interosseous soft tissue in the antebrachial area. On the basis of the successful outcome in this case, surgical excision of the interdiaphyseal callus and interposition of a polypropylene mesh could be a viable option for management of posttraumatic radioulnar synostosis in birds of prey.

Orthopedic infections in equine long bone fractures and arthrodeses treated by internal fixation: 192 cases (1990-2006).

OBJECTIVE: To determine the rate of postoperative infection (POI) for internal fixation repaired equine long bone fractures and arthrodeses and identify associated risk factors. STUDY DESIGN: Case series. ANIMALS: Horses (n=192) with fracture repair of the third metacarpal and metatarsal bones, radius, ulna, humerus, tibia, and femur, or arthrodesis with internal fixation. METHODS: Medical records (1990-2006) were reviewed for signalment, anatomic location, fracture classification and method of repair, technique and surgical duration, bacterial species isolated, postoperative care, onset of POI, and outcome. RESULTS: Of 192 horses (171 [89%] closed, 21 [11%] open fractures), 157 (82%) were discharged from the hospital. Infection occurred in 53 (28% horses), of which 31 (59%) were discharged. Repairs without POI were 7.25 times more likely to be discharged from the hospital. Closed fractures were 4.23 times more likely to remain uninfected and 4.59 times more likely to be discharged from the hospital compared with open fractures. Closed reduction and internal fixation was associated with a 2.5-fold reduction in rate of POI and a 5.9 times greater chance for discharge from the hospital compared with open reduction and internal fixation. Females had a strong trend for increased POI when compared with colts and stallion but not geldings. CONCLUSIONS: Overall rate of POI was 28%. Fracture classification, method of repair, gender, and surgical duration were significant risk factors.

Locking compression plate osteosynthesis of complicated mandibular fractures in six horses.

Complicated mandibular fractures were recognised in one foal, one pony and four horses. The foal was two months old while the adult animals ranged in age from 12 to 24 years. Three horses had a unilateral horizontal ramus fracture. Two fractures were open and one was closed. Comminution was present in one of these patients while the other two horses had marked displacement of the fragments. Two suffered from comminuted fractures of the horizontal and vertical ramus of the mandible. One of these patients had open and infected fractures. One foal had a bilateral horizontal ramus fracture with marked periosteal 'new bone' formation and malalignement which required corrective osteotomy. Each horse underwent locking compression plate (LCP) osteosynthesis consisting of open fracture reduction and application of one to three 4.5/5.0 mm LCP at the ventral, lateral or caudal aspect of the mandible under fluoroscopic control. Two 3.5 mm LCP were used in the foal. Plate fixation was supported by application of a cerclage wire construct between the incisor and premolar teeth in most patients. Complete fracture healing, with an excellent functional and cosmetic outcome, was achieved in all of the patients. Complications encountered included seroma formation, screw and wire breakage, as well as implant and apical tooth root infections. The LCP was removed after fracture healing had occurred in four patients.

Synthesis Pengo System plates for the treatment of long-bone diaphyseal fractures in dogs.

A Brazilian orthopaedic company designed a stainless steel plate called Synthesis Pengo System (S.P.S.), which has one fixed and one changeable extremity. According to the assembly of the changeable extremity, it is possible to obtain dynamization or neutralization of the fracture site. Since the S.P.S. plate was developed for use in human patients, the aim of this study was to evaluate this system in long-bone diaphyseal fractures in dogs. Eight dogs with closed diaphyseal fractures of the femur (n= 1), radius and ulna (n=5), and tibia (n=2) were used. Patients were aged seven months to three years and weighed 18 to 31.2 kg. The S.P.S. plate was assembled with one fixed extremity and one changeable extremity in dynamization mode. The trail bar was positioned for synthesis modules with holes for cortical screws. The modules were positioned close to one another in two fractures and far away from the fracture site in the others. The bone healing occurred by external callus. Since motion at the fracture site determines the amount of callus required, the secondary bone healing that was observed in all of the cases indicated less rigid fixation of this system. A potential benefit of this system was a lesser interface contact with the bone since it was only done by trail bar. The major disadvantage was the prominence of the implant. It was possible to conclude that the S.P.S. plate appears to be a suitable method for the treatment of diaphyseal fractures in dogs.

Complications after orthopedic surgery in alpacas and llamas: 24 cases (2000-2006).

OBJECTIVE: To report complications associated with orthopedic surgery in alpacas and llamas. STUDY DESIGN: Retrospective study. ANIMALS: Alpacas (n=18) and llamas (n=6) that orthopedic surgery using internal or external fixation. METHODS: Medical records (January 2000-December 2006) and radiographs were reviewed and owners contacted for follow-up information for alpacas and llamas that had orthopedic surgery involving internal or external fixation. Fourteen camelids had internal fixation, 7 had external fixation, and 3 had a combination of internal and external fixation. RESULTS: Twenty-two animals (92%) were discharged after surgery (mean hospitalization, 15 days). Of 20 animals with >or=1 year follow-up information, 18 were alive (82%). Postoperative complications related to fracture healing, infection, soft tissue structures, or joints occurred in 21 camelids (87%). Thirteen animals returned to their intended use, 4 animals returned to breeding but not their intended use, 4 were euthanatized, and 3 were only able to be used as pets. CONCLUSIONS: Fixation type (internal, external) did not have any significant effect on complications involving fracture healing, infection, soft tissue structures, or chronic lameness. Camelids with open fractures were more likely to have complications associated with fracture healing, repair, and infection than closed fractures. CLINICAL RELEVANCE: Complications after orthopedic surgery in alpacas and llamas are more common than previously reported and may result in chronic lameness or prevent return to their intended use.

Evaluation of closed reduction and screw fixation in lag fashion of sacroiliac fracture-luxations.

OBJECTIVE: To evaluate outcome by radiographic assessment after closed reduction and percutaneous screw fixation in lag fashion of sacroiliac fracture-luxations in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=24) with sacroiliac fracture-luxations. METHODS: Medical records (1999-2006) and radiographs of 24 dogs (29 fracture-luxations) that had stabilization of sacroiliac fracture-luxation by fluoroscopic-guided closed reduction and percutaneous screw fixation in lag fashion were reviewed. Signalment, body weight, number, and location of all concurrent injuries and implants used for repair were recorded. Radiographs were used to evaluate the accuracy of screw placement in the sacral body, screw depth/sacral width ratio, reduction of the sacroiliac joint, pelvic canal diameter, and hemipelvic canal width. Radiographic re-examination (range, 4 to >8 weeks postoperatively) was available for evaluation. RESULTS: Mean screw depth/sacral width ratio on immediate postoperative and re-examination radiographs was 64% and 61%, respectively. Mean percentage reduction of the sacroiliac joint on immediate postoperative and re-examination radiographs were 91% and 87%, respectively. Pelvic canal diameter ratio demonstrated successful restoration of the pelvic canal. Hemipelvic canal width ratio documented successful closed reduction repair independent of concurrent pelvic injuries. CONCLUSION: Successful repair of sacroiliac fracture-luxations, determined by radiographic assessment, can be achieved by fluoroscopic-guided closed reduction and percutaneous screw fixation in lag fashion. CLINICAL RELEVANCE: Fluoroscopic-guided closed reduction and percutaneous screw fixation in lag fashion of sacroiliac fracture-luxations is a minimally invasive technique that restores and maintains pelvic canal dimensions and should be considered as an alternative to open reduction or nonsurgical management of sacroiliac fracture-luxations.

The use of an external skeletal traction device for distal fractures in the dog. A clinical case series of 11 patients.

Metacarpal and metatarsal fractures in 11 patients were treated 'closed' with a specially designed External Skeletal Fixation (ESF) frame with a walking bar and traction applied to the digits. Mediolateral angulation had improved postoperatively in 10 of the 11 patients. Craniocaudal angulation had improved in eight patients and could not be evaluated in three due to ESF frame superimposition. At follow-up, eight patients had a good clinical function, whereas three patients were still slightly lame. Only minor ESF-related complications were seen (pin loosening, pin tract infection, cerclage wire breakage and bending of the frame), which resolved without intervention after frame removal.

Axial compression generated by cortical and cancellous lag screws in the equine distal phalanx.

Lag screw fixation using single 4.5 mm cortical bone screws is a recommended technique for repair of mid-sagittal plane fractures of the distal phalanx in adult horses. However, implant infection and technical difficulties in obtaining adequate interfragmentary compression have made this surgical procedure somewhat controversial. We hypothesized that use of larger diameter screws would result in increased axial compression and improved stability of this fracture. Paired distal phalanges from the forelimbs of 10 adult horses were collected at necropsy and divided in half in the midsagittal plane. Using a randomized block study design, four types of bone screws (4.5 mm cortical, 5.5 mm cortical, 6.5 mm cancellous pre-tapped, and 6.5 mm cancellous non-tapped) were inserted to a depth of 15 mm. During screw insertion, the axial force generated under the screw head was measured with a load washer containing a piezoelectric force transducer, while torque of insertion was recorded with a torsional testing machine. The 6.5mm screw inserted after pre-tapping generated significantly greater axial force (2781 N) than the 4.5 mm (1522 N), 5.5 mm (2073 N) or 6.5 mm non-tapped (2295 N) screws. The relationship between maximal applied torque and axial force generated was linear for each screw type. Each unit of torque applied during insertion of cortical screws resulted in a greater increase in axial compression, as compared to cancellous screws. These data suggest that use of larger diameter screws would result in improved interfragmentary compression of distal phalangeal fractures.

Reduction and stabilisation of a supraglenoid tuberosity avulsion under arthroscopic guidance in a dog.

A supraglenoid tuberosity avulsion fracture was diagnosed in a five-month-old dog, which was presented with a non-weightbearing lameness of the right forelimb after being involved in a road traffic accident. Arthroscopy allowed associated cartilaginous, capsular and ligamentotendinous injuries to be ruled out. The fracture was reduced and stabilised under arthroscopic guidance using a Kirschner wire and a cortical bone screw. Video assistance significantly minimised the extent of the necessary craniomedial approach. The lameness was very mild 15 days after surgery and had disappeared after four weeks. Radiographs taken nine weeks postoperatively revealed complete bone healing and implants were removed. No lameness was reported during a follow-up period of 20 months. To the authors' knowledge, this is the first report describing shoulder osteosynthesis under arthroscopic guidance in the dog. The mildly invasive character of arthroscopy and video-assisted surgical procedures may allow a faster recovery and may limit complications following the treatment of articular fractures.

A tension band technique for stabilisation of sacroiliac separations in cats.

A tension band technique was used in conjunction with a transarticular pin to stabilise 24 sacroiliac separations in 19 cats. The authors suggest that this technique is simpler and safer than the transarticular screw technique, and as effective.

Radial carpal bone fractures in 15 dogs.

Between 1977 and 1992, 15 adult dogs were presented to the Universities of Bristol, Glasgow, Liverpool and London with fractures of the radial carpal bone which had occurred without a known episode of violent trauma. Eleven of the dogs were boxers and the other breeds affected were a Pharaoh hound, rottweiler, springer spaniel and a greyhound. The condition was bilateral in three cases. Eleven dogs were treated surgically by cast immobilisation (four cases), fragment removal (one case), lag screw fixation (three cases), pan-carpal arthrodesis (one case) and lag screw reduction followed by pan-carpal arthrodesis (two cases). The remaining four dogs were treated conservatively with rest and tactical use of non-steroidal anti-inflammatory drugs. Follow-up periods ranged from two months to 11 years. Varying degrees of lameness, which tended to be exacerbated by exercise, persisted in all cases. The radial carpal bone appears to have at least three separate centres of ossification which eventually fuse; their planes of fusion correspond approximately to the two main fracture lines. These areas of fusion could be weak points within the radial carpal bone.

The use of a polypropylene mesh for treatment of ruptured collateral ligaments of the equine metatarsophalangeal joint: a report of two cases.

The prognosis of ruptured collateral ligaments of the metacarpophalangeal or metatarsophalangeal joint in horses is usually considered to be poor, especially for future athletic performance. The main problem is the development, due to joint instability, of osteoarthritis, which may result in persistent lameness. In this paper a surgical technique is described in which joint stabilisation is realised by using a polypropylene mesh as a substitute for the ruptured ligaments, with the subsequent application of a cast for 7 weeks. The technique was successfully performed in 2 horses with ruptured lateral collateral ligaments of a metatarsophalangeal joint. Fifteen months after surgery both horses resumed exercise. Performance could be classified as fair in one case and good in the other. It is concluded that the preliminary results obtained with this surgical technique to stabilise ruptured collateral ligaments of the fetlock joint are promising.

Detection of a radiographically occult fracture of the lateral palmar process of the distal phalanx in a horse using computed tomography.

A horse with a suspected injury of the distal phalanx was examined using radiography at day two and 19 after the onset of the lameness, with no definite diagnosis. Using computed tomography an incomplete fracture of the lateral wing of the distal phalanx was diagnosed at day 25. Based on computed tomography it was determined that the fracture probably did not enter the joint or involve the palmar cortex throughout its length which were of prognostic importance. The day following the CT examination a new oblique radiographic projection was made. In this radiography which was based on, and never would have been attempted without, the information about the geometric pattern of the fracture achieved by CT examination, a radiolucent area indicative of a wing fracture was seen. This report emphasizes the value of computed tomography in diagnosing a geometric complicated nonarticular oblique fracture of the palmar process of the pedal bone in a horse.

Closed reduction and lag screw fixation of sacroiliac luxations and fractures.

OBJECTIVE: To describe a technique for closed reduction and percutaneous insertion of a lag screw for fixation of sacroiliac fracture-luxations, and to report the success of this technique in stabilizing sacroiliac fracture-luxations. STUDY DESIGN: A retrospective clinical study. STUDY POPULATION: 13 consecutive client-owned dogs with sacroiliac fracture-luxations. METHODS: Sacroiliac fracture-luxations were stabilized by using a closed reduction and percutaneous lag screw fixation technique. Preoperative, postoperative, and last re-examination radiographs were used to assess the location and number of pelvic injuries, other orthopedic injuries, percent reduction of the sacroiliac joint, percent sacral width screw depth, position of the screw, pelvic canal diameter ratio, hemipelvic canal width ratio, and complications. Information on signalment, weight, weight-bearing status, neurologic status, and complications was obtained from the medical record. RESULTS: Mean percent reduction of the sacroiliac joint was 92.33%. All screws were placed within the sacral body with a mean screw depth/sacral width of 79.03%. No screw loosening occurred. Mean pelvic canal diameter ratios were 0.99, 1.20, and 1.14 preoperatively, immediately postoperatively, and at the last re-examination, respectively. Nine of 13 dogs were willing to walk on the ipsilateral rear leg the day after surgery. CONCLUSIONS: Closed reduction and percutaneous insertion of a lag screw for stabilization of fracture-luxation of the sacroiliac joint is an acceptable method of repair. CLINICAL RELEVANCE: Sacroiliac fracture-luxations can be successfully reduced and stabilized using a minimally invasive technique.