Short-term outcomes for surgical correction of feline medial patellar luxations via semi-cylindrical recession trochleoplasty.

Case series summary: Three cats (five stifles) were diagnosed with varying degrees of pelvic limb lameness secondary to medial patellar luxations (MPLs). Lameness did not resolve with medical management in any cat before referral for orthopedic evaluation. All cats underwent semi-cylindrical recession trochleoplasty (SCRT), medial fascial release and lateral imbrication for surgical repair of MPLs. All cats were re-evaluated at 3 and 8 weeks postoperatively and two cats were also evaluated at 16 weeks postoperatively. At the final rechecks, all cats had resolution of lameness of the operated limb(s) and no evidence of recurrence of patellar luxation. Relevance and novel information: This case series demonstrated SCRT with soft tissue reconstruction as an acceptable option for surgical correction in three cats with MPLs. Short-term outcomes revealed minor complications and all patellae remained centralized.

Cerebrospinal fluid lactate concentrations in dogs with seizure disorders.

BACKGROUND: Cerebrospinal fluid (CSF) lactate concentrations increase after seizure activity in many human patients independent of the underlying disease process. The effect of seizure activity on CSF lactate concentration in dogs is unknown. HYPOTHESIS/OBJECTIVES: Cerebrospinal fluid lactate concentration is unaffected by seizure activity in dogs and is more dependent on the underlying disease process causing the seizures. ANIMALS: One-hundred eighteen client-owned dogs with seizure disorders. METHODS: Case series. Cerebrospinal fluid lactate concentration was determined using a commercially available lactate monitor. Seizure semiology, time from last seizure to CSF collection, number of seizures within the 72 hours preceding CSF collection, and clinical diagnosis were recorded. RESULTS: Dogs with focal seizures had higher CSF lactate concentrations than did those with generalized seizures (P = .03). No differences in lactate concentrations were found among dogs with single seizures, cluster seizures or status epilepticus (P = .12), among dogs with CSF collection at different time points after the last seizure activity (P = .39) or among dogs having different numbers of seizures within the 72 hours preceding CSF collection (P = .42). A significant difference (P = .001) was found in CSF lactate concentrations among diagnostic groups, and dogs with inflammatory and neoplastic disease had higher concentrations than did dogs with idiopathic or unknown epilepsy. CONCLUSIONS AND CLINICAL IMPORTANCE: Cerebrospinal fluid lactate concentration is minimally affected by seizure activity in dogs and increased concentrations are more likely associated with the underlying disease process.

Long-term clinical and magnetic resonance imaging follow-up of dogs with osseous-associated cervical spondylomyelopathy.

BACKGROUND: Osseous-associated cervical spondylomyelopathy (OA-CSM) is a complex disorder with limited long-term survival. The longitudinal progression is currently unknown. OBJECTIVE: To describe changes on magnetic resonance imaging (MRI) over a 2-year minimum period. We hypothesized that spinal lesions would progress in the majority of dogs. ANIMALS: Eleven dogs previously diagnosed with OA-CSM were prospectively studied. Nine dogs were treated medically, whereas 2 were treated surgically. METHODS: Clinical and MRI follow-up were performed with a median time between MRI studies of 30 months (range, 24-54). Morphologic assessment evaluated vertebral canal stenosis, spinal cord compression, foraminal stenosis, and articular processes, among other variables. Morphometric assessment included vertebral canal area, spinal cord area, area of the articular processes, and foraminal height. RESULTS: On follow-up MRI, the most affected site at the initial examination in medically treated dogs had progressed in 4 of 9 dogs, improved in 4, and was unchanged in 3. Clinically, all dogs except 2 medically treated dogs were unchanged to improve at follow-up. Initially, 50 of 60 (83.3%) intervertebral spaces had vertebral canal stenosis, whereas in the follow-up MRI 82.3% did. Of the sites with stenosis, 45.7% were unchanged, 18.6% improved, and 38.9% worsened. Morphometry identified significant decreases in vertebral canal and spinal cord areas at C4-C5 through C6-C7, and significant progression of articular process irregularities at C3-C4 and C6-C7. CONCLUSIONS AND CLINICAL IMPORTANCE: This long-term follow-up study of dogs with OA-CSM did not identify clinical or MRI progression of lesions in the majority of dogs.

Progressive Myelomalacia in a Pomeranian Following Spinal Fracture and Surgical Stabilization-A Case Report.

A 4-year-old female spayed Pomeranian presented for being unable to use its pelvic limbs after a fall. The dog was paraplegic with absent pelvic limb nociception and a Schiff-Sherrington posture. Radiographs and Computed tomography showed a T11-T12 luxation. Spinal stabilization was performed for pain control. Twenty-four hours following surgery the patient lost pelvic limb reflexes. Twelve hours later she lost cutaneous trunci and forelimb proprioception and had increased respiratory effort. A diagnosis of progressive myelomalacia was made and the patient was euthanized. Most cases of progressive myelomalacia in dogs are due to intervertebral disc herniation. To the authors' knowledge, myelomalacia secondary to spinal fracture has not been reported.

Cerebrospinal fluid lactate in dogs with inflammatory central nervous system disorders.

BACKGROUND: Cerebrospinal fluid (CSF) lactate is frequently used as a biomarker in humans with inflammatory central nervous system (CNS) disorders including bacterial meningitis and autoimmune disorders such as multiple sclerosis. HYPOTHESIS: Cerebrospinal fluid lactate concentrations are increased in a subset of dogs with inflammatory CNS disorders. ANIMALS: One hundred two client-owned dogs diagnosed with inflammatory CNS disease. METHODS: Case series. Cases were identified both prospectively at the time of diagnosis and retrospectively by review of a CSF biorepository. Cerebrospinal fluid lactate was analyzed with a commercially available, handheld lactate monitor. Subcategories of inflammatory disease were created for comparison (eg, steroid-responsive meningitis arteritis, meningoencephalitis of unknown etiology). RESULTS: Cerebrospinal fluid lactate concentrations were above reference range in 47% of dogs (median, 2.5 mmol/L; range, 1.0-11.7 mmol/L). There was no significant difference in lactate concentrations between disease subcategories (P = .48). Significant but weak correlations were noted between CSF lactate concentration and nucleated cell count (r = .33, P < .001), absolute large mononuclear cell count (r = .44, P < .001), absolute small mononuclear cell count (r = .39, P < .001), absolute neutrophil cell count (r = .24, P = .01), and protein (r = .44, P < .001). No correlation was found between CSF lactate concentration and CSF red blood cell count (P = .58). There was no significant association of CSF lactate concentration with survival (P = .27). CONCLUSIONS AND CLINICAL IMPORTANCE: Cerebrospinal fluid lactate concentrations could serve as a rapid biomarker of inflammatory CNS disease in dogs.

Validation of a portable monitor for assessment of cerebrospinal fluid lactate in dogs.

BACKGROUND: Cerebrospinal fluid (CSF) lactate concentration may be a useful diagnostic and prognostic biomarker in dogs. Previous studies have used methods requiring relatively large sample volumes or prolonged storage prior to analysis. An effective method to immediately quantify lactate in smaller CSF volumes would be beneficial. OBJECTIVES: The main objectives were to evaluate the utility, accuracy, and precision of a portable meter for CSF lactate analysis in dogs and to develop a provisional RI using this device. A secondary objective was to assess the effects of different storage conditions on lactate concentrations. METHODS: The Lactate Plus device was used to analyze CSF samples. Device accuracy and precision were assessed by spiking CSF samples with concentrated sodium lactate solutions and by repeated analysis of samples, respectively. The provisional RI was generated using CSF samples from dogs with unremarkable laboratory data, central nervous system imaging, and conventional cytologic and chemical CSF analysis. Select samples were analyzed before and after storage at 4°C, -20°C, and -80°C. RESULTS: Spiked samples showed lactate concentrations comparable to expected concentrations. The CV of immediate repeated measurements was 0-9.69%. Sample storage at 4°C for 24 hours showed similar results but variation was higher with other storage conditions. The provisional RI was 1.02-2.49 mmol/L. CONCLUSIONS: The Lactate Plus has acceptable accuracy and precision for the quantification of CSF lactate in dogs. Lactate in CSF is ideally quantified immediately after collection as a subset of samples show variation with storage although most stored samples show acceptable variation.

Evaluation of the Lactate Plus monitor for plasma lactate concentration measurement in dogs.

OBJECTIVE: To compare the Lactate Plus handheld monitor to a reference blood gas analyzer for determining plasma lactate concentrations in canine whole blood. DESIGN: Prospective observational study. SETTING: University teaching hospital. ANIMALS: Ninety-four dogs hospitalized or admitted through the emergency service provided 125 blood samples. Only dogs that required a venous or arterial blood gas evaluation as a part of their diagnostic assessment or ongoing management were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Canine whole blood samples were assayed for plasma lactate concentration with a reference blood gas analyzer and the Lactate Plus monitor. Correlation and Bland-Altman analyses were used to compare results between the 2 methods. A subset of blood samples was repeatedly analyzed with the Lactate Plus to assess monitor precision. Plasma lactate measurements from the Lactate Plus monitor showed excellent correlation with those from the reference analyzer (ρ = 0.98, P < 0.0001). Bland-Altman analysis revealed a small bias (0.1296). Agreement between the 2 methods was less consistent for lactate concentrations >5 mmol/L. The coefficient of variation ranged from 0-26.2% (median, 3.7%) and was <15% for 50/53 samples. CONCLUSIONS: The Lactate Plus provides a fast and affordable method to measure plasma lactate concentration in dogs. Results showed excellent agreement with the reference analyzer and precision of the instrument was acceptable.