Comparison of the Diagnostic Value of Ultrasonography and Standing Radiography for Pelvic–Femoral Disorders in Horses

Objective— To assess agreement between ultrasonography (transcutaneous and transrectal) and standing radiography in horses with fractures in the pelvic region and disorders of the coxofemoral joint.
Study Design— Case series.
Animals— Warmblood horses (n=23) and 2 ponies.
Methods— Medical records (1999–2008) of equids with pelvic or coxofemoral disorders that had pelvic radiography and ultrasonography were retrieved and results of both techniques compared.
Results— Radiography and ultrasonography each identified equal numbers of fractures of the tuber coxa (n=4), ilial shaft (2), ischium (3), femoral neck (2), and osteoarthritis/osis of the coxofemoral joint (6). Fractures of the ilial wing (4) were only identified by ultrasonography not by standing radiography. Of 9 acetabular fractures, 3 were identified on radiographs only, 5 were identified with both modalities. One pubic fracture was identified using ultrasonography and radiography. One acetabular and 1 pubic fracture were only diagnosed on necropsy.
Conclusions— We found reasonable agreement (73%; 24/33) between ultrasonography and standing radiography for diagnosis of pelvic–femoral disorders. Ultrasonography was more useful for ilial wing fractures and radiography for acetabular fractures.
Clinical Relevance— Ultrasonography is a rapid, safe imaging technique for detecting disorders of the pelvic region with a high diagnostic yield and is a preferred initial approach in horses with severe hindlimb lameness.     

A technique for pelvic radiography in the standing horse

REASONS FOR PERFORMING STUDY: An alternative technique of radiographing the pelvis in the standing horse is required, to avoid the risks associated with general anaesthesia. HYPOTHESIS: That lateral oblique radiography in the standing horse would be a useful technique in the investigation of pelvic injury. OBJECTIVES: To describe the technique of lateral oblique pelvic radiography in the standing horse and demonstrate the feasibility and usefulness of this technique. METHODS: A technique for lateral oblique radiography in the standing horse was devised and retrospective review made of radiographic findings in 18 clinical cases. RESULTS: The caudal iliac shaft, greater trochanter of the femur, femoral head, acetabulum and coxofemoral articulation on the side under investigation were visualised consistently using this technique. Of the 18 cases, 3 iliac shaft fractures, 1 acetabular fracture, 2 coxofemoral luxations and 4 horses with new bone formation around the coxofemoral joint and/or proximal femur were identified. CONCLUSIONS: Lateral oblique radiography in the standing, conscious horse can be used to investigate conditions affecting the caudal iliac shaft, coxofemoral articulation and proximal femur in the horse. POTENTIAL RELEVANCE: The technique is straightforward, noninvasive and useful in the investigation of horses with suspected pelvic injury. However, not all pelvic injuries would be identified, and normal radiographic findings do not rule out injury or fractures elsewhere in the pelvis.     

Orthopaedic disease affecting the pelvic region of the cat

Clinical cases of pelvic disease in the cat were surveyed over a 5 year period and were classified into proximal femoral epiphyseal separation and femoral neck fracture (19-6%), anterodorsal hip luxation (19-6%), pelvic fracture (34%), sacroiliac separation (16%), sacral and coccygeal fracture separation (7-2%) and neoplasia (3-1%).
Treatment of proximal femoral epiphyseal separation and femoral neck fracture by excision arthroplasty gave a more rapid return to soundness compared with conservative treatment. The majority of hip luxations responded well to external reduction and restricted exercise for 2-4 days. All cases of pelvic fract. ure were treated conservatively (2-14 days of 'cage-rest') and showed marked improvement within 2 weeks. Radiographic and clinical assessment of these revealed that the fractured bones eventually stabilized in their displaced positions. Sacral and coccygeal fracture separations required careful evaluation for bladder function and some cases needed tail amputation. Certain complications associated with conservative treatment of pelvic injuries in cats have been considered although in no case did these prove a serious clinical problem. Two cases of giant cell sarcoma and one of spindle cell sarcoma, of periosteal origin, were included in the survey.     

Fractures of the femur in newborn calves

A retrospective study of femoral fractures in 77 calves revealed that most occurred in the femoral shaft or in the proximal physis, with thin cortices and periosteal stripping significant problems in fractures of the femoral shaft. Most cases were related to forced extraction, with more left femurs being affected than right. The existence of concurrent disease reduced the success rate by 50% and, when significant additional trauma was present, no calves survived. When all cases were considered regardless of condition, the “longterm” success rate was 43%.     

Femoral capital physeal fractures in dogs: 34 cases (1979-1989)

Complications associated with femoral capital physeal (CP) fractures in 34 dogs were evaluated. Fractures were surgically repaired, using divergent K-wires or lag screws; radiographic follow-up was available for 21 CP fractures. In all cases, radiographic abnormalities such as degenerative joint disease and resorption of the femoral neck and/or head were seen. Changes were more severe when fracture occurred at an early age. For 4 of 21 dogs (20%), femoral head and neck excision was performed because of complications associated with CP fracture repair. Prognosis for femoral CP fractures is guarded, although affected dogs should be able to function as pets.     

Use of flexible intramedullary rods for fixation of femoral fractures in eight dogs

High-density, polysulfone rods were used to repair 4 comminuted and 4 short-oblique, mid-diaphyseal femoral fractures in 8 dogs. Bony union was achieved in 2 dogs at 10 and 12 weeks after surgery. In one dog, the femoral fracture was healing when amputation of the limb became necessary because of sciatic nerve damage secondary to an ipsilateral pelvic fracture. In a fourth dog, fracture repair resulted in nonunion, despite normal clinical function at 18 months after surgery. In the remaining 4 dogs (50%), the rods failed at 3.5, 4, 6, and 22 weeks after surgery. These fractures were then stabilized by use of other methods. Although several factors may have contributed to failure of the rods, multiple autoclaving of the thermoplastic implants may have caused embrittlement and subsequent breakage.     

Technetium-99m-HDP uptake characteristics in equine fractures: a retrospective study

Bone scintigraphy is a very sensitive diagnostic tool to detect elevated bone metabolism. In cases of fractures and fissure fractures, the radiopharmaceutical uptake in the bone is said to be increased within a few hours after the injury. In this retrospective study, the scintigraphic uptake characteristics at the fracture site of 36 horses with radiographically confirmed fractures or fissure fractures were evaluated. Uptake ratios between the fracture region and adjacent normal bone or soft tissue activity respectively were calculated and compared to different anamnestic and radiographic data. The overall sensitivity of bone scintigraphy was 94.4% (34 positive cases out of 36). In the 36 horses, no correlation between the age of the fracture and the radiopharmaceutical uptake was found. However, there seems to be a lack of sensitivity in early detection of equine pelvic fractures when a standing bone scintigraphy examination protocol is used.     

Femur fractures associated with canine total hip replacement

OBJECTIVE: To report femur fracture as a complication of canine total hip replacement (THR) and to report the incidence, predisposing factors, treatment options, and outcome. STUDY DESIGN: Prospective clinical study. ANIMALS: Twenty-two client-owned dogs with 24 femoral fractures occurring during or after THR. METHODS: Cemented THR (BioMedtrix, Boonton, NJ) was performed. Medical records and radiographs were used to identify dogs that had femur fracture and to identify risk factors. Follow-up was obtained until dog death or study end. RESULTS: The overall incidence of femur fracture after THR was 2.9%. Femoral fractures occurred intraoperatively, immediately postoperatively, and up to 2196 days after THR. In 17 dogs, fractures resulted from a traumatic event. Osteopathy was present at THR in 5 dogs; all developed femoral fissures during reaming. Three dogs had fractures associated with cortical thinning secondary to aseptic loosening. Fracture treatment included euthanasia (1 dog), strict confinement (3 dogs), full cerclage wires on long oblique fractures (3 dogs), or plate and screw fixation (10 with, and 7 without, cerclage wires). All fractures extended near the distal tip of the femoral stem and all aggressively treated fractures healed. CONCLUSIONS: Predisposing risk factors for femur fracture after THR include osteopathy and iatrogenic fissures created during reaming. Trauma, excessive load concentration, and increased torque can lead to mid-diaphyseal fracture near the end of the femoral stem. Fracture did not disrupt THR implants. Cement fracture exposing the tip of the femoral stem did not affect fracture healing or rehabilitation. Immediate plate and screw fixation resulted in the most favorable outcome; healing occurred in 6-10 weeks. CLINICAL RELEVANCE: Femur fractures that occur after THR should be repaired using plate and screw fixation augmented with cerclage wire when needed. Forces on fissures should be neutralized to prevent propagation and fracture. Owners of high-risk patients (old dogs with osteopathies or previous hip surgery) should be counseled before THR. The prognosis is excellent when fractures are treated correctly.     

Effect of triple pelvic osteotomy on the proximal femoral geometry in dysplastic dogs

Triple pelvic osteotomy (TPO) is one of the surgical procedures for use to try to reduce subsequent degenerative joint disease or modify the progress of hip dysplasia in young dogs. Joint force and pressure distribution were changed by this procedure. Therefore, the aim of this study was to find out whether the remodeling of proximal femur exists or not after TPO in dysplastic dogs. Ten femora from five young dysplastic mongrel dogs, treated unilaterally with TPO using 20° canine pelvic osteotomy plates, were used. One year after TPO, neck-proximal shaft angle, femoral head, neck, diaphyseal and mid-shaft diameters, total femoral, femoral neck axis, and intertrochanteric, femoral head offset lengths as well as the lengths from head center to lateral margin of greater trochanter and to proximal femoral axis were measured from the bone. The significant differences between treatment and control side were determined in Norberg angle, neck-proximal shaft angle, neck diameter, diaphyseal diameter, mid-shaft diameter, length from head center to proximal femoral axis and femoral head offset length. In conclusion, although small number of cases was used, it was determined that the aforementioned variables are affected by TPO. So, these variables may be supply additional information about the changes to the joint following TPO in dysplastic dogs.     

Femoral Fracture Repair Using a Locking Plate Technique in an Adult Captive Polar Bear (Ursus Maritimus)

Objective— To report successful femoral fracture repair in a polar bear. Study Design— Case report. Animals— Female polar bear (Ursus maritimus) 5 years and ～250 kg. Methods— A closed, complete, comminuted fracture of the distal midshaft femur was successfully reduced and stabilized using a compression plating technique with 2 specialized human femur plates offering axial, rotational, and bending support, and allowing the bone to share loads with the implant. Postoperative radiographs were obtained at 11.5 weeks, 11 months, and 24 months. Results— Bone healing characterized by marked periosteal reaction was evident at 11 months with extensive remodeling evident at 24 months. No complications were noted. Conclusions— Distal mid shaft femoral fracture was reduced, stabilized, and healed in an adult polar bear with a locking plate technique using 2 plates. Clinical Relevance— Previously, femoral fractures in polar bears were considered irreparable. Use of 2 plates applied with a locking plate technique can result in successful fracture repair despite large body weight and inability to restrict postoperative activity.     

NAVICULAR BONE FRACTURE IN THE PELVIC LIMB IN TWO HORSES

The case history, radiographic and scintigraphic findings of two horses with pelvic limb navicular bone fractures are presented. In both cases the fractures were of traumatic origin. One horse had a bilateral fracture of the navicular bone, distal border, the other horse had a fracture of the proximal articular border in one pelvic limb navicular bone.     

Treatment of tibial fractures with plates using minimally invasive percutaneous osteosynthesis in dogs and cats

OBJECTIVES: The aim of the here described case series was to develop and evaluate the minimally invasive percutaneous osteosynthesis for the plate fixation of tibial fractures in dogs and cats. METHODS: Six dogs and four cats with shaft fractures of the tibia were treated using minimally invasive percutaneous osteosynthesis. Follow-up radiographs four to six weeks after fracture fixation were evaluated for fracture healing. For the long-term follow-up (minimum 2.4 years), owners were contacted by phone to complete a questionnaire. RESULTS: All fractures healed without the need for a second procedure. Follow-up radiographs obtained after four to six weeks in seven cases showed advanced bony healing with callus formation and filling of the fracture gaps with calcified tissue in all seven. All the patients had a good to excellent long-term result with full limb function. The time needed for regaining full limb use was two to three months. CLINICAL SIGNIFICANCE: Minimally invasive percutaneous osteosynthesis seems to be a useful technique for the treatment of tibial shaft fractures in dogs and cats.     

Occurrence and pattern of long bone fractures in growing dogs with normal and osteopenic bones

A retrospective study was undertaken to record the occurrence and pattern of long bone fractures, and the efficacy of Intramedullary (IM) Steinmann pin fixing in growing dogs. All the records of growing dogs during a 10-year-period were screened to record the cause of trauma, the age and sex of the animal, the bone involved, the type and location of the fracture, the status of fixation, alignment, maintenance of fixation and fracture healing. The results were analysed and comparisons were made between growing dogs with normal and osteopenic bones. Among the 310 cases of fractures recorded, the bones were osteopenic in 91 cases (29%). Minor trauma was the principal cause of fracture in dogs with osteopenia (25%), and indigenous breeds were most commonly affected (38%). Fractures in dogs with osteopenic bones were most commonly recorded in the age group of 2-4 months (53%), whereas fractures in normal dogs were almost equally distributed between 2 and 8 months of age. Male dogs were affected significantly more often in both groups. In osteopenic bones, most fractures were recorded in the femur (56%), and they were distributed equally along the length of the bone. Whereas in normal bones, fractures were almost equally distributed in radius/ulna, femur and tibia, and were more often recorded at the middle and distal third of long bones. Oblique fractures were most common in both groups; however, comminuted fractures were more frequent in normal bones, whereas incomplete fractures were more common in osteopenic bones. Ninety-nine fracture cases treated with IM pinning (66 normal, 33 osteopenic) were evaluated for the status of fracture reduction and healing. In a majority of the cases (61%) with osteopenic bones, the diameter of the pin was relatively smaller than the diameter of the medullary cavity (<70-75%), whereas in 68% of the cases in normal bones the pin diameter was optimum. The status of fracture fixing was satisfactory to good in significantly more osteonormal (59%) than osteopenic dogs (42%). Fracture healing, however, was satisfactory in significantly more cases with osteopenic than normal bones. The appearance of callus was relatively early and the amount of bridging callus was relatively large in greater number of osteopenic bone fractures. Mal-union and non-union were recorded more often in osteopenic cases than in normal cases. However, the incidence of bone shortening and osteomyelitis was significantly higher in normal bones than in osteopenic bones.     

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.     

Risk Factors for Femoral Fracture after Canine Press‐Fit Cementless Total Hip Arthroplasty

Objective: To evaluate risk factors for femoral fracture after porous‐coated cementless total hip arthroplasty (THA). Study Design: Case series. Animals: Dogs (n=74) that had cementless THA (n=84). Methods: Medical records of dogs from 2 referral hospitals were reviewed for occurrence of postoperative femoral fracture. Patient and operative (age, breed, sex, weight, and canal flare index [CFI], indication for arthroplasty, intraoperative fissure, cerclage usage, and implant sizes) factors were analyzed. Assessment of implant positioning and canal fill was performed on immediate postoperative radiographs. Femoral fractures (n=11) were evaluated and compared with 73 cases without fracture that met the inclusion criteria. Results: Mean (±SEM) age was 7.30±0.69 years for dogs with, and 4.77±0.37 years for dogs without femoral fracture. Age was positively associated with fracture (P=.022). Mean (±SEM) CFI was 1.80±0.09 for dogs with, and 1.98±0.04 for dogs without fracture. CFI was negatively associated with fracture (P=.045). Body weight, intraoperative fissure, cerclage use, implant size, position, and canal fill did not influence the occurrence of femoral fracture. Conclusions: Older dogs and dogs with lower CFI may be at increased risk for femoral fracture after porous‐coated cementless THA. Clinical Relevance: Risk factors exist for femoral fracture after cementless THA using porous‐coated implants, and should be critically evaluated during the patient selection. These risks should be weighed against the benefits of the system, and measures to minimize femoral fracture in at‐risk patients studied.     

ABNORMAL IMAGING FINDINGS OF THE FEMORAL THIRD TROCHANTER IN 20 HORSES

Injuries involving the femoral third trochanter are an uncommon but important source of equine lameness; however, clinical localization can be challenging. The purpose of this retrospective study was to describe ultrasonographic and scintigraphic findings in a group of horses with presumed third trochanter injury. Medical records of an equine referral hospital were searched from 2004–2014, and 20 horses met the inclusion criteria. Lesions consistent with third trochanter fracture were identified with ultrasound in 14/20 horses. Onset of lameness was acute (11), insidious (2), or unknown (1). All but one horse was lame at presentation, ranging from Grade 2–4/5. Ultrasound was the primary diagnostic modality in 5/14 horses with fragmentation, while scintigraphic findings of intense (3), moderate (5), and mild (1) increased radiopharmaceutical uptake (IRU) prompted ultrasonographic examinations in 9/14 fractured horses. A nondisplaced fracture was suspected in an additional horse with intense IRU and negative ultrasound findings. In the remaining five horses, imaging findings included only mild IRU. Lameness was localized to other regions in these cases. Six of 12 fractured horses with available outcome data were returned to function after a prolonged rehabilitation of 8–18 months. Scintigraphic findings helped to direct focused ultrasound exams in the majority of fracture cases. Horses with evidence of third trochanter fracture had similar clinical characteristics to that reported for pelvic fractures and authors therefore recommend ultrasonographic examination of both regions, especially when scintigraphy is unavailable. Prognosis for return to function in horses of the current study was less favorable than previously reported.     

Management of fractures and exostosis of the metacarpals and metatarsals II and IV in 25 horses

Twenty-five cases of fractures of the second and fourth metacarpal and metatarsal (splint) bones were reviewed. Fourteen fractures involved a thoracic limb and 11 involved a pelvic limb. Fractures of the proximal one-third of splint bones are reported in one of two forms: fractures that are closed, or fractures with a permanent or intermittent draining sinus. Thirteen of the fractures presented were closed fractures and the remaining 12 were open. All of the closed fractures were managed by surgical excision of the distal fragment and the exostosis at the fracture site, followed by primary surgical wound closure. Lag screw fixation of the proximal fragment was used in three cases. All of the open fractures were managed surgically by excision of the distal splint fragment and debridement of the contaminated fracture site. Primary wound closure was used in 11 of the 12 cases. All closed fractures healed by primary intention, and 10 of 13 were free from lameness at one year follow-up. The 11 open wounds which were operated and subsequently closed under suture healed by primary intention. The wound left open healed by granulation, scar contraction, and epithelialisation. Eight of these horses were sound one year later. The remainder of the open fractures were lost to follow-up.     

Use of IMEX SK-circular external fixator hybrid constructs for fracture stabilization in dogs and cats

Complex long-bone fractures with short juxta-articular fracture segments can be difficult to manage. Recently, IMEX Veterinary, Inc., began producing titanium hybrid rods that can be secured to ring components of the IMEX circular external skeletal fixation system to create SK-circular hybrids. In this case series, SK-circular hybrids were used to stabilize long-bone fractures (two femoral, one humeral, and three tibial fractures) with short distal bone segments in three dogs and three cats with body weights ranging from 1.9 to 15 kg (mean, 6.7 kg; median, 5.4 kg). Although three cases required surgical revision, animals ambulated well and all fractures obtained union. Time to radiographic union ranged from 62 to 137 days (mean, 90 days; median, 84 days). The functional outcome was considered excellent in all six cases.     

Open reduction and internal fixation with a locking plate for the treatment of a femoral fracture in a ferret (Mustela putorius furo)

Long bone fractures in ferrets (Mustela putorius furo) are usually traumatic in etiology, and the femur is commonly affected [1]. A 4-year-old, castrated male ferret was examined for acute, non-weight-bearing lameness of the left pelvic limb after presumably falling from its elevated enclosure. Clinical and radiographic evaluation showed a complete, comminuted fracture of the proximal diaphyseal third of the left femur. Open reduction and internal fixation (ORIF) of the left femoral fracture was performed with cerclage wires and a 1.5 mm locking compression plate with associated locking screws. Anatomic reconstruction was achieved, and postoperative radiographs confirmed appropriate fracture fragment apposition, limb alignment, and implant placement. At 9 weeks postoperatively, the ferret was ambulatory with no evidence of lameness, and complete radiographic union was noted. This is the first published report of the use of a bone plate for femoral fracture stabilization in a ferret. Bone plates, including locking plates, could be considered for long bone fracture stabilization in ferrets as an alternative to other methods.