Subchondral bone cyst of the apical portion of the proximal sesamoid bone as a cause of severe lameness in a Warmblood filly

A 20‐month‐old Warmblood filly was evaluated for acute onset of a nonweightbearing lameness and swelling of the left hindlimb. Clinical and lameness evaluation and diagnostic intrasynovial anaesthesia isolated the lameness to the left hind metatarsophalangeal region. Radiography and ultrasonography revealed a subchondral cystic lesion of the apical portion of the lateral proximal sesamoid bone associated with oedema and synovial effusion of the metatarsophalangeal joint. Arthroscopic surgical debridement of the subchondral cystic lesion resulted in immediate post operative improvement in the lameness score. Rest and controlled exercise achieved complete resolution of the lameness with the filly being able to start training without apparent lameness. Subchondral cystic lesions of the proximal sesamoid bones can be a cause of nonweightbearing lameness. Surgical debridement resulted in complete resolution of the lameness with a favourable outcome in this case.     

Acute suprarenal occlusion in an American Miniature Horse

A 7-month-old Miniature filly was examined because of a 4-day history of abnormal posture, lethargy and weakness. On initial evaluation, the filly presented with an abnormal stiff gait in her hindlimbs associated with hindlimb ataxia and lumbar kyphosis. She showed hindlimb discomfort by weight shifting from one hindlimb to the other. A complete blood count revealed an acute inflammatory leukogram associated with hyperfibrinogenaemia. The measurement of the serum amyloid A concentration indicated anactive inflammatory process. Biochemistry and urinalysis results revealed a severe azotaemia associated with diluted urine despite clinical dehydration, consistent with acute renal failure. Medical treatment was initiated with fluid therapy and antimicrobials. The pain was managed with morphine sulphate only, to avoid further kidney damage. The filly maintained an abnormal gait during this time, became progressively more ataxic and uncomfortable, and developed colic episodes. Because the horse was unresponsive to pain management, euthanasia was elected by the client. Post-mortem examination revealed an occlusive thrombus within the abdominal aorta, firmly attached to the intima, partially recanalised and extending from the aorta 1 cm along the right renal artery. In the left and right kidneys, severe subacute neutrophilic pyelonephritis, with lymphoplasmacytic interstitial nephritis was noted. In the hindlimb muscles, multifocal myocyte necrosis and evidence of regeneration was present. To the authors’ knowledge, this is the first case of acute suprarenal occlusion to be described in a horse.     

Bilateral avulsion fracture (apophyseolysis) of the calcaneal tuber in a heifer

This case report describes the clinical, radiographic, ultrasonographic and histopathological findings of a six-month-old heifer, suffering from bilateral fracture of the calcaneal tuber caused by osteochondrosis. The young cattle was admitted to the clinic for the evaluation of a left hindlimb lameness, having persisted for several weeks. Orthopaedic examination revealed a highly stilted gait with a lameness of the left hind limb, so severe that the heifer was only able to put some weight on the tip of the toe. The calcaneal region on both hindlimbs showed a diffuse swelling, palpation being very painful. The radiological examination revealed a fracture of the calcaneal tuber (apophyseolysis) of both hindlimbs.     

Treatment of a Cyst-Like Synovial Hernia Associated with the Digital Flexor Tendon Sheath of a 17-Year-Old Pony

The aim of this study is to describe the successful treatment of a synovial hernia associated with the digital flexor tendon sheath (DFTS) in a 17-year-old pony. The pony presented with left forelimb lameness and multiple unusual swellings of the palmar and plantar aspect of the fetlock. The lameness was isolated to a swelling in close proximity to the DFTS of the left forelimb using diagnostic analgesia, and on diagnostic imaging, the swelling was found to be associated with the DFTS. The hernia resolved after percutaneous drainage and intralesional corticosteroids and atropine and pressure bandaging. Reports of synovial hernias in the horse associated with the DFTS are rare. This difference should be considered when presented with cases exhibiting similar clinical signs.     

Are ovine fenugreek (Trigonella foenum‐graecum) staggers and kangaroo gait of lactating ewes two clinically and pathologically similar nervous disorders?

Fenugreek staggers has occurred in sheep in Victoria, as both an acute and a chronic syndrome. Signs included quadraparesis, a high stepping fore limb gait and a 'bunny-hopping' hind limb gait. Changes consistent with acute oedema were found in the brain and spinal cord of acute cases, and Wallerian degeneration in the peripheral nerves of chronic cases. Kangaroo gait occurred in ewes in New South Wales, and the clinical signs and microscopic changes were remarkably similar to those of fenugreek staggers. Although the diet associated with each is different the causal agent may be the same.     

Secondary malignant lymphoedema after mastectomy in two dogs

This case report describes the diagnosis of secondary malignant lymphoedema in two dogs that had undergone a mastectomy. A remarkable severe oedematous lesion associated with lameness in the right hindlimb was observed in both cases. Diagnostic imaging examinations, including direct pedal lymphangiography (case 1) and lymphoscintigraphy (case 2), showed obstruction of lymph flow in the lymphatics of the right hindlimbs. Although the recommended medical management and physiotherapy had been applied to resolve the problems, oedema did not improve in the damaged region in both cases. Results of histopathological examinations suggested that the cause of the obstructed lymph flow was neoplastic cells in the lymphatics of the right hindlimb in both dogs.     

Staphyloccocus aureus-associated infarctive purpura haemorrhagica,immune-mediated haemolytic anaemia and myocarditis in a Quarter Horse mare

A 7-year-old Quarter Horse mare was presented for severe left hindlimb oedema and nonweightbearing lameness that was progressive over approximately 48 h. The mare subsequently developed marked and worsening oedema, immune-mediated haemolytic anaemia (IMHA), myositis and myocarditis. The marked oedema, degree of pain and severity of myositis were consistent with infarctive purpura haemorrhagica. Fine needle aspiration of affected tissue resulted in positive bacterial culture of Staphylococcus aureus. Purpura haemorrhagica and associated complications are typically associated with Streptococcal sp. infection or exposure, and have not been previously reported in association with Staphylococcus aureus in the horse. The mare responded favourably to long-term, high-dose corticosteroid therapy, antimicrobials and supportive care.     

Anaerobic bacterial infections causing osteomyelitis/arthritis in a dog.

A 3-year-old German Shepherd Dog was examined for lameness, signs of pain, swelling, a draining fistulous tract, and osteolysis after a dog bite on the left carpus. After failure of the lesion to respond to several antibiotics, Peptostreptococcus sp and Propionibacterium sp were isolated from swab specimens and then from surgically collected bone and soft tissue specimens. The bone fragments had mild purulent osteomyelitis associated with numerous gram-positive rods and cocci. The dog was successfully treated by surgical debridement of the lesion and clindamycin administration.     

Acute intervertebral disc extrusion in a cat: clinical and MRI findings

A 5 year old, neutered male, domestic shorthaired cat had acute left hemiparesis and Horner's syndrome. Magnetic resonance imaging (MRI) revealed a loss of the normal signal from the nucleus pulposus of the intervertebral disc at C3/4, narrowing of the ventral subarachnoid space and slight dorsal displacement of the spinal cord and a focal hyperintense lesion affecting the left side of the spinal cord at the same level. The presumptive diagnosis was focal spinal cord oedema associated with intervertebral disc extrusion. A traumatic aetiology was suspected. The cat was treated conservatively and improved gradually over a period of 6 months.     

Suspected fibrocartilaginous embolism in a cat

A 12-year-old cat was presented to the University of Queensland's Small Animal Teaching Hospital with a 1-day history of left hemiparesis of acute onset, with no evidence of trauma or toxin exposure. Neurological examination findings were consistent with a lesion in the caudal left cervical spinal cord (C6 to C8), which was non-painful and had not progressed since the onset of clinical signs. No other abnormalities were found, although myelography showed a mild swelling involving the caudal cervical and cranial thoracic spinal segments. A diagnosis of suspected fibrocartilaginous embolism was made on the basis of the history, clinical presentation and diagnostic tests results, making this case the first report of a suspected fibrocartilaginous embolism in a cat that returned to normal function.     

ACANTHOMATOUS AMELOBLASTOMA OF THE MAXILLA OF AN ADULT ALPACA

An adult alpaca presented with a large maxillary swelling. Facial trauma or a tooth root abscess was suspected. Radiographically there was a large expansile lesion displacing the right maxillary teeth. An ameloblastoma was diagnosed histologically and palliative radiation therapy was attempted. Because of poor response to therapy and anorexia the animal was euthanized. Necropsy findings confirmed an ameloblastoma of acanthomatous type.     

Multicentric T‐cell lymphoma presenting as inferior palpebral swelling in a Standardbred mare

A 6‐year‐old Standardbred mare that presented with bilateral palpebral swelling and a left corneal ulcer was diagnosed with a multicentric T‐cell lymphoma. Other clinical findings included submandibular lymphadenopathy and oedema, pharyngeal oedema and rhinitis. Prior to euthanasia the horse developed keratomalacia, the onset of which was coincidental with the use of high doses of topical and systemic corticosteroids. Although an unusual presentation, palpebral swelling should be considered as a clinical sign of lymphoma.     

Long-term survival after surgical excision of a schwannoma of the sixth cervical spinal nerve in a dog

A schwannoma of the sixth cervical spinal nerve in a 5-year-old Shetland Sheepdog was surgically excised, sparing the thoracic limb and resulting in long-term survival. The dog had been referred because of slowly progressive left thoracic limb lameness. The lesion was localized to the left suprascapular and musculocutaneous nerves or the C6 and C7 spinal nerves on the basis of neurologic examination, electrodiagnostic examination, and myelography. Surgical exploration revealed a mass, which was excised and identified histologically as a schwannoma. Three and a half years later, the dog was normal except for mild gait abnormality, focal muscle atrophy, and a focal area of decreased cutaneous sensation of the left thoracic limb.     

Alternative surgical treatment for synovial ganglion cyst of the digital tendon sheath in one horse

A 6-year-old Highland pony gelding was presented with severe left fore (LF) limb lameness of acute onset. The lameness occurred concomitantly with mild digital flexor tendon sheath (DFTS) effusion and focal painful swelling on the lateral aspect of the LF fetlock region. Clinical examination and diagnostic analgesia localised the lameness to the fetlock region and on ultrasound, a cyst-like structure filled with anaechoic fluid was detected just proximal to the lateral sesamoid bone, at the proximo-lateral aspect of the DFTS and adjacent to the lateral neurovascular bundle. Communication between the cyst-like structure and the DFTS was suspected ultrasonographically and then confirmed with contrast tenography. Tenoscopic examination of the LF DFTS was performed and the communication between the fluid-filled structure and the synovial cavity was detected. The defect in the DFTS wall was enlarged tenoscopically and the lining of the cyst-like structure was debrided. The horse recovered well post-operatively and was back in work with no evident lameness 8 months after surgery. This alternative minimally invasive surgical treatment had an excellent outcome and has the advantage of reducing the risk associated with en bloc resection.     

Severe hindlimb lameness and pathological femur fracture in a horse secondary to haemangiosarcoma

An 18‐year‐old Warmblood stallion was presented for an acute onset nonweightbearing right hindlimb lameness following a mild lameness of 2 weeks' duration. Severe swelling was present in the right femoral area. Despite extensive diagnostic procedures, no definitive diagnosis could be made. Packed red cell volume was persistently low. The horse improved with supportive treatment and was discharged at the owner's request. The horse presented 4 days later for bleeding from a previously made incision on the lateral femoral area. Due to deterioration of his condition, the stallion was subjected to euthanasia. Diagnosis of disseminated haemangiosarcoma, affecting primarily the hindlimb musculature and leading to pathological fracture of the femur was made at necropsy and subsequent histopathology.     

PARTIAL AVULSION OF THE ORIGIN OF THE CRANIAL CRUCIATE LIGAMENT IN A 4 YEAR-OLD DOG

A four year-old intact male Dalmatian was referred to the veterinary teaching hospital at Louisiana State University for acute, non-weight-bearing left hindlimb lameness of three weeks duration. Information supplied by the referring veterinarian indicated the lameness was first diagnosed and treated seven months previously, but recurred three weeks ago. External rotation of the left stifle, mild discomfort upon stifle flexion, mild to moderate muscle atrophy and palpable joint effusion were noted during physical examination. Slight cranial drawer movement with a soft end-point was discovered during manipulation of the left stifle. A triangular bone fragment and thickened, confluent intracapsular soft tissues were observed on radiographs of the stifle. Radiographically, moderate degenerative changes suggested chronicity. This report describes the clinical and radiographic findings of a rarely reported partial avulsion of the origin of the cranial cruciate ligament in a skeletally mature dog.     

An unusual cyst‐like lesion in the metaphysis of the tibia in a horse

A 6‐year‐old Haflinger gelding was presented with a chronic right hindlimb lameness. Scintigraphy, radiography and computed tomography confirmed an active large cyst‐like lesion in the distal metaphysis of the right tibia. A transcortical surgical approach was used to curette the lesion and fill it with an autologous bone graft and a calcium phosphate bone substitute material. Histopathology revealed mild histiocytic inflammatory changes, mild fibrosis and bone necrosis. This case report describes an unusual cyst‐like lesion in the tibial metaphysis of a horse.     

Septic tenosynovitis of the tarsal sheath of an Arab gelding and suspected sepsis of the lateral digital flexor tendon subsequent to bacterial peritonitis

A 21-year-old Arab gelding with clinical signs of acute peritonitis had a perforating ulcer on the mesenteric border of the jejunum which resulted in localised contamination of the abdomen with ingesta. The affected segment of jejunum was resected and the abdomen was lavaged extensively. Postoperatively, the gelding was treated with broad-spectrum antibiotics, non-steroidal anti-inflammatory drugs and intravenous fluids, but after four days it became acutely non-weight bearing on its right hindlimb, and a tendonitis of the lateral digital flexor tendon within the tarsal sheath was identified ultrasonographically. The septic tendonitis was treated with broad-spectrum antibiotics but progressed proximodistally within the tendon until it involved both the tarsal sheath and the associated tarsocrural joint, necessitating the euthanasia of the gelding.     

Carpal hyperextension in a Percheron mare caused by a palmar carpal ligament tear

A Percheron mare was presented for acute, severe lameness and marked swelling of the right forelimb after being cast. The mare was initially diagnosed with cellulitis of the forelimb but as her condition improved and the affected limb was able to bear more weight it became apparent that the limb was hyperextended at the level of the carpus. Widening of the palmar aspect of the middle carpal joint was observed radiographically. During ultrasonographic examination, excessive fluid in the carpal sheath and perithecal swelling were noted and tearing of the palmar carpal ligament was suspected. A dynamic brace was fabricated to prevent hyperextension of the carpus. After discontinuation of systemic antibiotics, the mare became febrile and forelimb lameness worsened. Cytology of fluid from the middle carpal joint confirmed joint sepsis and the mare was anaesthetised for arthroscopic examination. A tear in the palmar carpal ligament, characterised by focal fibre disruption and fibrillation, was identified during arthroscopic and tenoscopic examination. Communication between the carpal flexor tendon sheath and middle carpal joint was identified during these procedures. Both the middle carpal joint and carpal flexor tendon sheath were lavaged with physiological saline solution. Post operatively, swelling and lameness slowly resolved. Four months after discharge, the mare was sufficiently sound to be maintained at pasture. Viewed from its lateral aspect, the limb no longer appeared to be hyperextended from the carpus.     

What is your diagnosis? Pancytopenia in a dog

Abstract: A 4‐year‐old male, castrated, mixed‐breed dog was presented to the Colorado State University Veterinary Teaching Hospital with a 1‐week history of polyuria, polydipsia, lethargy, fever, inappetence, weight loss, and soft mucoid stool. The dog was depressed and had pale, icteric mucous membranes. Results of a CBC included normocytic, normochromic, nonregenerative anemia, neutropenia, and thrombocytopenia, with 43% blast cells (200/μL), many of which contained fine azurophilic granules. Cytologic evaluation of the bone marrow aspirates revealed mild granulocytic hyperplasia that appeared to be left‐shifted in an apparent maturation arrest. A large population of blast cells comprised 35% of nucleated cells; the blasts had high nuclear to cytoplasmic ratios, deeply basophilic cytoplasm with vacuoles, and prominent nucleoli. Most cells also contained many fine azurophilic granules clustered in the paranuclear region. At necropsy, neoplastic cells were abundant in the bone marrow. Immunohistochemically the cells expressed CD3?, and an oligoclonal T‐cell rearrangement was found. The diagnosis was proliferative disorder of CD3⁺ granular lymphocytes, with associated pancytopenia. Because the blast cells were morphologically similar to myeloblasts and immunohistochemistry was required to confirm the diagnosis, T‐cell lymphoproliferative disease should be considered in dogs with pancytopenia presenting with similar clinical features.