Instantaneous center of rotation in the canine femorotibial joint: Ex vivo assessment of a tool to evaluate joint stabilization surgeries.

Cranial cruciate ligament rupture is a common cause of femorotibial joint instability in the dog. Numerous techniques including several tibial osteotomies have been described for stabilization, but there is no current consensus on the best method. The instantaneous center of rotation (ICR) can aid investigations of pathological joint movement, but its use is problematic in the femorotibial joint due to combined rotation and translation during flexion and extension. Using fluoroscopic images from an earlier cadaveric study of canine joint stability, an interpolation method was used to create repeatable rotational steps across joint situations, followed by least squares approximation of the ICR. The ICR in intact joints was located mid-condyle but displaced significantly (P < 0.001) proximally following cranial cruciate ligament transection and medial meniscal release. Individual joints appear to respond differently to destabilization. Triple tibial osteotomy partially restored ICR location during early movement from flexion to extension. Joint instability significantly altered the proportions of rolling and gliding movement at the joint surface (P < 0.02), which triple tibial osteotomy partially improved. While triple tibial osteotomy restores joint stability ex vivo and clinically, normal biomechanics of the joint are not restored. The methods described here may prove useful for comparison of osteotomy techniques for stabilization of the cranial cruciate ligament deficient femorotibial joint in dogs.

Reported accuracy of cranial closing wedge ostectomy variants for management of canine cranial cruciate ligament insufficiency: A systematic review and meta-analysis.

Concerns have been raised about the predictability of achieving appropriate tibial plateau angles (TPA), the occurrence of axis shift and tibial length reduction following cranial closing wedge ostectomy (CCWO). The primary objective of this review was to quantify typical errors in achieving target TPA with CCWO, with secondary objectives of assessing axis shift and length reduction. Retrospective or prospective studies of CCWO used as the primary treatment, from any date and in English, were eligible for inclusion. Searches were performed in EMBASE, Ovid MEDLINE, Agricola, Scopus, Web of Science, and CAB abstracts. Risk of bias was assessed, and data were screened for outliers and influential cases. Extracted data from 11 included studies were tabulated and underwent meta-analysis using R. Mean errors in TPA after CCWO ranged from - 0.6-2.9°, indicating the possibility of both under- and over-correction depending on the selected technique. Errors were relatively consistent for technique subgroups. Mean axis shifts ranged from 3.4° to 5.2°, and length reduction ranged from 0.4% to 3.2% of initial length, based on 6/11 and 3/11 studies, respectively. Data had high heterogeneity, many studies had small populations, and reporting standards were inconsistent. Concerns about the predictability of postoperative TPA may be overstated. With the limited data available, limb shortening does not appear to be a clinically important consideration. Axis shift will occur to varying degrees and must be considered during CCWO planning, as it influences the postoperative TPA. Careful choice of CCWO technique may allow clinicians to reliably achieve predictable TPA values.

Oestrus status does not alter breeding suitability assessments regarding medial patellar luxation in female small breed dogs: A blinded multi-observer study.

Study aims were to evaluate if medial patellar luxation clinical grades changed with oestrus status, and to determine interobserver agreement for different classification methods for grading patellar luxation. Intact female dogs were recruited for grading by 3 independent observers on 2 occasions (pro-oestrus/oestrus and dioestrus/anoestrus) using a published grading system. Observers were blinded to oestrus status. Oestrus status was confirmed by vaginal cytology. Observer agreement was determined using Fleiss' multirater kappa on the original grading scores, simplification to the Norwegian Kennel Club system, and further simplification to a binary suitable/not-suitable for breeding system. The exact McNemar's test was used to assess the effect of oestrus on classification. Of 70 dogs recruited, 53 underwent paired observations. Interobserver agreement was considered moderate to very good for the study sub-groups, with overall kappa values of 0.68 (95% CI 0.63-0.72), 0.79 (0.73-0.84) and 0.92 (0.85-0.99), and percentage agreements of 65%, 81% and 94%, for the original, simplified and binary classifications. Oestrus status did not have a significant effect on classification of breeding suitability. Clinicians and owners should not be concerned about the timing of patellar luxation grading in relation to oestrus. Experienced observers show good or very good agreement using the Norwegian Kennel Club and binary categorisations.

Geometric modelling of error sources for tibial plateau levelling osteotomy in the dog.

Tibial plateau levelling osteotomy is widely performed for stabilization of cranial cruciate ligament deficient stifles in dogs. A wide range of postoperative tibial plateau angles around the target angle has been reported. The main aim of this study was to investigate if osteotomy placement could explain this range. Landmarks were derived from 50 tibial radiographs by five observers and used to define osteotomy placement and correction angles for simulation. Observer-specific osteotomy locations with mean landmark data were used to simulate planning errors, and simulated malpositioning of the osteotomy at 5 mm and 10 mm from the ideal location was used to simulate surgical errors. The tibial plateau midpoint was used as the ideal centre of the osteotomy in this model. Planning errors mostly arose from tibial plateau misidentification, with osteotomy centre locations dispersed up to 2.4% of tibial length from ideal. Malpositioning of the osteotomy resulted in variable changes in tibial plateau angle. Synthesis with historical data suggested such changes are likely limited in magnitude in tibiae with a mechanical axis length over 140 mm, but will be greater in smaller dogs and with steeper tibial plateaus. In medium to large breed dogs, our findings indicate osteotomy inaccuracy alone cannot explain the reported postoperative ranges in tibial plateau angles. Other error sources such as rotational inaccuracies or shifts during implant placement may be more significant. Surgeons should exercise additional caution when operating small and miniature breeds due to the much larger potential for clinically significant errors in these smaller dogs.

Geometric modelling of CORA-based levelling osteotomy in the dog.

Centre of rotation of angulation (CORA)-based levelling osteotomy (CBLO) is a recent addition to surgical procedures for stabilization of the cranial cruciate ligament-deficient canine stifle joint. Careful identification of the CORA location preoperatively and use of this location intraoperatively are required to ensure accurate correction of the tibial plateau angle. Limited data are available regarding the magnitude and source of potential errors during planning and execution of CBLO. A geometric model enabling isolation of various error sources is described. Landmarks were derived from tibial radiographs (n = 50) by 5 observers and used to define proximal and distal anatomical axes for simulation of CBLO. Observer-specific CORA locations with mean landmark data were used to assess planning errors, and simulated malpositioning of the CORA at 10 mm from the ideal location was used to assess surgical errors. Planning errors result mainly from tibial plateau misidentification, with CORA locations dispersed up to ±10 mm proximodistally from ideal (95% confidence). Malpositioning of the CORA during surgery causes equal and opposite changes in tibial plateau angle (TPA) and anatomical-mechanical axis angles, and varying degrees of translation and limb length changes. The magnitude of these changes is dependent on initial TPA and limb length, with smaller dogs and steeper tibial plateaus resulting in larger errors. Optimal planning and execution are required to achieve the planned outcome of CBLO. The main source of error in our simulation is identification of the tibial plateau. While both pre- and intraoperative errors influenced TPA, based on our geometric model the effect in larger dogs may not be clinically significant. If distalisation of the CORA is required during surgery, compensation of the CORA angle to maintain the target TPA is possible.

Immunometabolic parameters in overweight dogs during weight loss with or without an exercise program.

The influence of physical activity on metabolic health in overweight dogs is unknown. This study was conducted to evaluate biomarkers of immunometabolic health in relation to changes in physical activity and adiposity. Client-owned overweight dogs participated in a 12-wk intervention based on caloric restriction combined with a training program (fitness and diet [FD] group, n = 8), or caloric restriction alone (diet-only [DO] group, n = 8). Physical activity was monitored by accelerometry. All dogs were fed the same diet and achieved similar weight loss. Fasting blood samples were collected before and after 6- and 12-wk intervention. Insulin resistance was evaluated from plasma insulin and C-peptide as well as homeostasis model assessment. Inflammation and dyslipidemia were evaluated from circulating leptin, adiponectin, C-reactive protein (CRP), monocyte chemoattractant factor-1 (MCP-1), interleukin-8 (IL-8), and cholesterol. Accelerometer counts in both groups were high compared with previous reports of physical activity in overweight dogs. No difference in blood parameters was evident between groups, evaluated by linear mixed-effects model (P > 0.05). Within the groups, the following changes were significant by t-test (P < 0.05): leptin decreased in both groups. Within the FD group, IL-8, MCP-1, and CRP decreased at 6 wk and IL-8 and cholesterol at 12 wk. Within the DO group, C-peptide and HOMA decreased at 6 wk and C-peptide at 12 wk. We conclude that, for both groups, weight loss resulted in minor indications of improved immunometabolic health, whereas this level of physical activity did not add further benefits.

A comparison of anatomical lateral distal femoral angles obtained with four femoral axis methods in canine femora.

OBJECTIVES: To report the repeatability and reproducibility of four different anatomical proximal femoral axis (a-PFA) methods for measuring anatomical lateral distal femoral angle (a-LDFA), and to compare a-LDFA values produced by each method at three different femoral elevation angles. METHODS: Digital radiographs were obtained of seven dry canine femora at 0°, 12.5° and 25° elevations. Using image analysis software, landmarks defining four different a-PFA and the condylar axis were identified by two independent observers on two separate occasions. Corresponding a-LDFA were calculated for each femur, elevation and a-PFA. Repeatability and reproducibility parameters were calculated and compared statistically, along with the effect of technique and elevation on a-LDFA value. RESULTS: Interobserver repeatability coefficients were subjectively better for three of the a-PFA methods at 2° compared to the fourth at 3.1°. Median a-LDFA increased significantly (p ≤ 0.002) with increasing femoral elevation for all a-PFA methods, with a median increase of 3.3°. The median difference in a-LDFA between a-PFA methods yielding the highest and lowest measurements was 2.6° over all three elevations. CLINICAL SIGNIFICANCE: The combined effects of a-PFA choice, femoral elevation and measurement reproducibility may produce typical errors of ± 2.6°, which could have implications for the selection of candidates for corrective osteotomies. Clinicians need to be aware that values obtained with one method and femoral elevation may not be equivalent to values obtained with other methods or elevations.

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.

Antifeedant and mosquitocidal compounds from Delphinium x cultorum cv. Magic fountains flowers.

Six volatile compounds, ethylmethylbenzene (1), 1-isopentyl-2,4, 5-trimethylbenzene (2), 2-(hex-3-ene-2-one)phenylmethyl ketone (3), E and Z isomers of 3-butylidene-3H-isobenzofuran-1-one (4 and 5), and 2-penten-1-ylbenzoic acid (6), were isolated from the mosquitocidal hexane extract of Delphinium x cultorum cv. Magic Fountains flowers. In addition, the ethyl acetate extract, which displayed corn earworm antifeedant activity, yielded 4-hydroxybenzoic acid (7) and bis(4-hydroxyphenyl)methanol (8). However, compounds 7 and 8 were not biologically active.

The art of pharmacotherapy in depressed outpatients.

There is an art to prescribing medications to depressed patients. Both patient and therapist factors are important to a successful outcome with appropriate timing and prescribing of treatment. Two case reports are provided as examples. Specific strategies used by experienced clinicians are presented in the discussion.

A comparison of the safety and efficacy of alprazolam and desipramine in moderately severe depression.

Fifty-four patients (34 outpatients, 20 inpatients) fulfilling Research Diagnostic Criteria for Definite Major Depressive Disorder were enrolled in a double-blind study comparing the antidepressant effects of alprazolam versus desipramine. The mean daily dose of alprazolam and desipramine at study termination was 3.78 mg and 208 mg respectively. As there were no significant demographic or clinical differences between outpatients and inpatients, both groups were combined in data analysis. Using the Hamilton Depression Rating Scale (HAM-D) both drug groups showed highly significant improvement beginning with the first week of active drug treatment. HAM-D scores continued to decrease through study termination (six weeks of active drug). There were no significant differences when comparing alprazolam and desipramine (outpatients, inpatients, or both groups combined) on any of the subjective or objective psychometrics used in this study. Clinically, only twelve of thirty-four outpatients (35.3%) were felt to be "markedly or moderately" improved, suggesting that neither the outpatient alprazolam nor desipramine patients did particularly well with drug treatment. In terms of drug safety there was no difference between the alprazolam and desipramine in the number of excessive or serious drug side effects. However, five of twenty-nine alprazolam patients had to discontinue therapy because of excessive drowsiness, and two of the alprazolam outpatients had motor vehicle accidents directly related to this adverse event. Alprazolam appeared as effective as desipramine in the pharmacotherapy of this group of depressed outpatient and inpatients. Alprazolam appeared well-tolerated by most subjects although drowsiness was a common--and at times serious--medication side effect.

The psychiatric referral in dentistry: indications and mechanics.

Psychiatric consultation is sometimes a part of the diagnostic evaluation of facial pain. The indications for referral arise out of the history. Several brief questions may indicate whether or not a psychiatric illness is present. Patients may hold beliefs or attitudes about their illness or about psychiatric treatment that make referral difficult. Successful referral depends on the relationship that the dentist establishes with the patient. Recommendations to facilitate the referral are presented.

A comparative study of bupropion and amitriptyline in depressed outpatients.

A double-blind controlled trial comparing a standard antidepressant drug, amitriptyline, with a new compound, bupropion, was conducted at six centers. There was a placebo washout, after which patients were assigned in a randomized fashion to one of the two treatments. No significant difference was found in therapeutic response to the two drugs after 4 weeks of treatment. Anticholinergic and cardiovascular side effects were less common in the bupropion-treated patients.

Ineffective dental and surgical treatment associated with atypical facial pain.

Patients with atypical facial pain (AFP) are subject to ineffective dental and surgical procedures for their pain complaints. Twenty-one of fifty-eight patients (36.2 percent) with AFP had sixty-five dental and surgical treatments, with only one patient showing less pain as a result of the treatment. While the majority of patients (69 percent) with AFP suffered from a psychiatric illness, fourteen (24 percent) of the patients referred for AFP had a specific medical or dental disorder that was causal in their pain complaints. There is a trend for the AFP patient with a psychiatric diagnosis to receive more ineffective treatments than those AFP patients for whom a specific medical or dental diagnosis was made. Patients with AFP should receive conservative dental and medical treatment and a psychiatric assessment before dental and surgical procedures are contemplated.

How to become comfortable talking about sex to your patients.

Dealing with patients' sex-related complaints is uncomfortable for many physicians. It can become more comfortable if the physician learns to apply his or her clinical knowledge of sexuality in combination with specific interpersonal interviewing skills. The level of comfort can be increased if the physician accepts his or her professional limitations in providing therapy and knows what other sources of care are available.

Psychiatric disorders associated with atypical facial pain.

Atypical facial pain (AFP) patients classically present with a chronic discomfort that is neither anatomic nor dermatomal in distribution. Neuropsychiatric assessment of 68 patients with AFP indicated that 46 (68%) had a specific psychiatric disorder by DSM-III criteria. A wide spectrum of psychiatric disorders was present. The authors emphasize that psychiatric assessment of patients with AFP should be an integral part in early assessments of this disorder, rather than relying on psychiatric opinions after extensive dental and other invasive procedures have been tried in vain and often to the detriment of the patient. Comments on the excellent prognosis in treating the psychiatric syndromes associated with AFP are made.

Clinical aspects of xerostomia.

The physiology of saliva flow and hyposalivation is discussed. Drug-induced hyposalivation results in a higher incidence of dental caries, causes discomfort for denture wearers, and increases the risk of oral infections. Guidelines for preventing and treating drug-induced xerostomia are offered.