Plate failure by bending following tibial fracture stabilisation in 10 cats.

OBJECTIVE: To describe the clinical findings and management of tibial fractures in cats in which osteosynthesis failed due to plate bending. METHODS: Case records and radiographs of cat tibial fracture repairs from five referral centres were reviewed for signalment and to assess incidence of plate failure by bending. Cats that sustained plate bending following plate or plate-rod fixation were reviewed for fracture configuration, repair method, initial postoperative and postfailure tibial alignment, revision treatment and outcome. RESULTS: The incidence of plate bending in cat fractures managed with plate and plate-rod fixation in the four referral centres where the overall number could be established was 13% (8/60). In the 10 cats in which plates bent, initial fractures were generally oblique or spiral with mild comminution and located in the middle or distal third of the tibia. Mean time to implant failure was 24 days (range 2 to 56 days). Mean tibial valgus angle increased from 12·9° to 30·9° following bending of the plate. Short-term outcome following revision surgery using orthogonal plating or stacked medial plates was favourable with improvement in tibial valgus in all five fractures with follow-up data. CLINICAL SIGNIFICANCE: Plate bending following tibial fracture stabilisation in these 10 cats resulted in tibial valgus deformation. Consideration of plate and/or intramedullary rod selection and application should be given to avoid a plate strain environment that exceeds the yield point of the plate.

Intra-articular mepivacaine reduces interventional analgesia requirements during arthroscopic surgery in dogs.

OBJECTIVES: To document efficacy of intra-articular mepivacaine in dogs based on the hypothesis that this would blunt the haemodynamic response to a nociceptive stimulus (arthroscopic surgery), reducing interventional analgesia requirements. METHODS: A dose of mepivacaine 2% 0 · 1 ml/kg (2 mg/kg) was injected intra-articularly into one randomly assigned elbow joint before surgery in eight dogs undergoing bilateral elbow arthroscopy. Baseline haemodynamic measurements were recorded immediately before the start of each arthroscopic procedure and repeated at arthrocentesis, saline distension of the joint, incision, arthroscopic cannula and obturator insertion and placement of the second portal and haemodynamic variability calculated. If baseline parameters increased by more than 20% suggesting nociception, 1 µg/kg fentanyl was administered intravenously. RESULTS: Significantly less fentanyl was required during arthroscopy on the mepivacaine treated elbows compared to the non-treated elbows (P = 0 · 003) and the time to first fentanyl administration was significantly longer (P = 0 · 0001) in the mepivacaine treated elbows (21 · 2 ± 4 · 9 minutes) compared to the non-treated elbows (6 · 1 ± 2 · 3 minutes). Haemodynamic variability was significantly reduced in the mepivacaine group (heart rate P = 0 · 04, mean arterial pressure P = 0 · 003). CLINICAL SIGNIFICANCE: Intra-articular mepivacaine blunts the haemodynamic response to arthroscopic surgery in dogs and reduces interventional analgesia requirement.

Effect of signalment on the presentation of canine patients suffering from cranial cruciate ligament disease.

OBJECTIVE: To determine the effect of signalment on the incidence and presentation of patients suffering from cranial cruciate ligament disease. METHODS: Data relating to 426 dogs (44 breeds) that met specific selection criteria were obtained from the hospital archive (2002 to 2008). Cases were followed up for 2 years. RESULTS: The breeds most commonly presented with cranial cruciate ligament disease were Labrador retriever (16%), Rottweiler (15%), golden retriever (12%) and boxer (9%). Rottweilers were significantly more likely (69%; P=0·05) to develop and present with (50%; P=0·03) bilateral cranial cruciate ligament disease. Rottweilers presenting with cranial cruciate ligament disease were significantly younger (median 977 days; P<0·0001) than other breeds; golden retrievers being significantly older at presentation (median 1994 days; P=0·004). Neither sex nor neutered status significantly affected the incidence of developing (P=0·77 and P=0·30, respectively) or presenting with (P=0·62 and P=0·35, respectively) bilateral cranial cruciate ligament disease. Entire dogs were significantly younger than neutered dogs at presentation (P=0·0004). Entire female dogs presented significantly younger than neutered females (P=0·0002), entire males (P=0·01) and neutered males (P=0·0001). CLINICAL SIGNIFICANCE: Breed affects the incidence of developing and presenting with bilateral cranial cruciate ligament disease. Breed and sex both affect the age that patients present with cranial cruciate ligament disease.

Arthroscopic partial patellectomy in a dog.

A six-year-old, female, neutered, whippet was presented for evaluation of a severe, sudden-onset right pelvic limb lameness. The extensor mechanism of the right stifle was intact and there was periarticular swelling in the right stifle. Radiography showed a fracture of the distal pole of the patella. The distal fragment was approximately 25% of the patellar length and the fracture was deemed non-reconstructable. Fracture fragment removal was performed arthroscopically, which led to an excellent clinical outcome. The owner considered the dog to be exercising normally at the seven-month postoperative examination. To the authors' knowledge this report documents the first arthroscopically performed partial patellectomy in veterinary surgery.

Arthroscopic-assisted management of osteochondritis dissecans in the stifle of a cat.

An 11-month-old, male neutered, domestic short-haired cat presented for evaluation of sudden onset right pelvic limb lameness. Radiography showed features consistent with unilateral osteochondritis dissecans (OCD) of the lateral femoral condyle in the right stifle. Arthroscopic examination of the stifle was used to confirm the presence of an articular cartilage lesion and the presence of loose cartilage within the joint. The loose cartilage fragments were removed arthroscopically. One arthroscopy portal was extended into a limited arthrotomy, which was necessary to ensure complete debridement of the defect. Removal of the fragments led to complete resolution of the clinical signs. This case report documents a more minimally invasive technique for the management of stifle OCD in the cat than previously documented and helps to establish a protocol for arthroscopic surgery in the feline stifle.

Partial tarsal arthrodesis and botulinum toxin A injection for correction of tarsal arthrogryposis in a cat.

An 11-week-old, domestic shorthair cat was presented for evaluation of a congenital right tarsal deformity. The cat was non-weightbearing lame on the right hindlimb. There was severe tarsal hyperextension and concurrent spasticity/contracture/shortening of the gastrocnemius muscle-tendon. The cat was otherwise healthy. Radiographically there was luxation of the proximal intertarsal joint and talocrural hyperextension. Treatment with 10 mu/kg botulinum toxin A (Botox; Allergan) intramuscular injections directly into the gastrocnemius muscle and passive physiotherapy marginally improved the range of motion in the talocrural joint. Definitive surgical treatment with partial tarsal arthodesis produced an excellent clinical outcome. This case report demonstrates the successful treatment of a severe congenital tarsal abnormality and also documents the first clinical use of botulinum toxin in a feline patient.

Long-term survival after combination chemotherapy for bilateral renal malignant lymphoma in a dog.

CASE HISTORY: A 6-year-old, entire male Flat-coated Retriever was presented with a history of lethargy, polydipsia and seizures. Clinical chemistry had shown marked azotaemia. CLINICAL FINDINGS AND DIAGNOSIS: Radiography and ultrasonography revealed bilateral renomegaly, and cytology of fine needle aspirates from the kidneys was diagnostic of malignant lymphoma. The dog was treated with a modified high-dose cyclophosphamide-, vincristine-, and prednisolone-based chemotherapy protocol, achieved remission, and returned to normal quality of life. Survival time was 346 days from the time of diagnosis. CLINICAL RELEVANCE: Malignant lymphoma in the kidneys of dogs has been considered to carry a uniformly poor prognosis. Long-term remission after medical treatment has not previously been reported. The favourable outcome in this case illustrates the limitations of clinical staging in determining the outcome for individual patients.

Congenital phimosis in a cat.

An 8-week-old domestic shorthair cat was presented with a history of pollakiuria and polydipsia. No abnormalities were detected during the clinical examination other than the penis could not be extruded from the prepuce. Urine culture demonstrated a growth of E. coli, which was treated with a prolonged course of amoxycillin. The polydipsia resolved and the pollakiuria improved but did not completely abate after antibiotic treatment and the cat had occasional bouts of haematuria. Because of the history of pollakiuria and polydipsia and the ongoing, occasional bouts of haematuria, the cat underwent surgical correction of the congenital phimosis. A small wedge of the dorsal prepuce was removed and the ipsilateral edges of the prepuce were apposed using a simple interrupted pattern. The procedure was quick, easy to perform and led to a resolution of the occasional bouts of haematuria and pollakiuria.

Oropharyngeal stick injury in a Bengal cat.

A 16 month old cat presented with a history of acute onset oral pain and hypersalivation. Oral examination revealed a wooden stick that protruded from the right sublingual region. Lateral cervical radiography showed retro pharyngeal gas lucencies. An 11 cm wooden stick was removed per os and the resulting tract was endoscopically explored. There were no post-operative complications and the cat remains disease free four months after presentation. In contrast to dogs, where oropharyngeal stick injuries are an uncommon albeit well recognised condition, there have been no previous case reports of oropharyngeal stick injuries in the cat. This case report describes the presentation, diagnosis and treatment of an oropharyngeal stick injury in a cat.