Development and Efficacy of a Canine Pelvic Limb Model Used to Teach the Cranial Drawer and Tibial Compression Tests in the Stifle Joint.

Canine cranial cruciate ligament rupture (CCLR) is the most common cause of pelvic limb lameness in dogs. CCLR results in palpable stifle instability secondary to cranial translation of the tibial relative to the femur, and it can be diagnosed during the orthopedic exam using the cranial drawer test (CDT) and tibial compression test (TCT). Accurate diagnosis of CCLR depends on the efficacy in performing these tests. In this study, two three-dimensional canine pelvic limb models were developed: one simulating a normal stifle and one simulating CCLR. Thirty-eight veterinary student participants answered questionnaires and performed both the CDT and TCT on a randomly assigned model. Twenty-one participants also manipulated the models one week later to assess skill retention in the short term. Mean levels of reported confidence in diagnosing CCLR and finding anatomic landmarks for CDT/TCT were significantly higher following model manipulation. Nearly all participants reported that they desired a model for teaching the diagnosis of CCLR. Most participants (92.5%) felt that the tested model would be useful for teaching CCLR diagnosis. Accuracy in diagnosing CCLR with the TCT significantly improved over time. Participant response indicated that while the tested model was effective and desirable, an ideal model would be more durable and lifelike. Further studies are needed to evaluate the developed models' effectiveness for teaching CCLR diagnosis compared to traditional teaching methods.

Systematic review of surgical treatments for cranial cruciate ligament disease in dogs.

Surgery for cranial cruciate ligament disease is often recommended; however, it is unclear if one procedure is superior. The aim of this systematic review was to answer the a priori question, "Is there a surgical procedure that will allow a consistent return to normal clinical function in dogs with cranial cruciate ligament disease and is that procedure superior to others?" A systematic literature search was performed through September 2013. Peer reviewed publication in the English language and 6 mo of postoperative follow-up were required. In total, 444 manuscripts were identified and reviewed, and 34 met the inclusion criteria. Two studies provided level 1, 6 provided level 2, 6 provided level 3, and 20 provided level 4 evidence relative to the study question. The most common surgical procedures included tibial plateau leveling osteotomy (TPLO, n = 14), lateral extracapsular suture (n = 13), tibial tuberosity advancement (n = 6). The strength of the evaluated evidence most strongly supports the ability of the TPLO in the ability to return dogs to normal function. It also provided strong support that functional recovery in the intermediate postoperative time period was superior following TPLO compared with lateral extracapsular suture. There was insufficient data to adequately evaluate other surgical procedures.

A systematic review of the literature describing the efficacy of surgical treatments for canine hip dysplasia (1948-2012).

OBJECTIVE: To systematically evaluate the literature reporting outcome of surgical treatments for canine hip dysplasia (CHD) and to evaluate whether adequate evidence exists to support a procedure that will allow a consistent return to normal function. STUDY DESIGN: Systematic literature review. ANIMALS: Dogs with naturally occurring CHD. METHODS: An a priori question was defined and a computer-based bibliographic search was performed on PubMed, Medline, CAB Abstracts, and Veterinary Information Network through November 2012. Studies were compared and evaluated with regard to surgical technique, study design, outcome measurements, evidence classification, and evidence quality. Unilateral surgeries with >6 months postoperative follow-up were included. RESULTS: Manuscripts (n = 477) were identified and reviewed; 17 met the inclusion criteria. One study provided level I evidence, 2 provided level II evidence, 3 provided level III evidence, and 11 provided level IV evidence relative to the study question. The most common outcome measurements were orthopedic examination (70.6%), owner interview (70.6%), and visual gait observation (64.7%). Three studies used objective kinetic gait assessment. Two studies with level III evidence (total hip replacement) and 1 study with level IV evidence (juvenile pubic symphysiodesis) documented a consistent return to normal function after surgery. CONCLUSIONS: Despite a large number of publications describing clinical outcome after surgical treatments for CHD, few provided strong evidence to allow an adequate assessment of therapeutic efficacy.

Surgical correction of angular and torsional metatarsal deformity with cylindrical osteotomy and locking compression plates in a calf.

OBJECTIVE: To report successful surgical correction of concurrent angular and torsional metatarsal deformities in a calf using a cylindrical osteotomy and locking compression plate (LCP) technology. STUDY DESIGN: Case report. ANIMALS: A 10-week-old composite bull calf. METHODS: Using Paley's principles of angular limb deformity correction, a cylindrical osteotomy was performed to concurrently correct varus deformity and external torsion of the metatarsus. The limb was aligned and stabilized using two 3.5 mm broad LCP with locking head screws. RESULTS: The calf was immediately weight bearing after surgery and did not experience any postoperative complications. Follow-up radiographs 5 months postoperatively revealed complete osteotomy healing and remodeling. The limb was in good alignment, the calf was fully weight bearing, and client satisfaction was very high. Telephone follow-up with the owner 16 months after surgery revealed continued full use of the operated limb and the bull was being used in a pasture breeding program. CONCLUSIONS: Cylindrical osteotomy with LCP stabilization can provide a favorable outcome in angular and torsional metatarsal deformity correction in cattle.

Accuracy of tibial osteotomy placement using 2 different tibial plateau leveling osteotomy jigs.

OBJECTIVE: To report the accuracy of osteotomy position in dogs undergoing tibial plateau leveling osteotomy (TPLO) and to evaluate the effect of 2 different TPLO jig and saw systems on tibial osteotomy position. STUDY DESIGN: Retrospective case series. ANIMALS: Dogs (n = 124; 134 TPLO). METHODS: Medical records (2004-2005; 2008-2011) and stifle radiographs of 2 groups of dogs that had TPLO to treat cranial cruciate ligament disease were reviewed. One group had a TPLO performed using an alignment jig system alone (Slocum group), whilst in the other group, an alignment jig system combined with a saw guide (Synthes group) was used. Postoperative radiographs were examined and the distance and direction of the centroid of the osteotomy was compared to the intended osteotomy position. RESULTS: The absolute distance of eccentricity (DOE) in the Slocum group (5.6 ± 2.5 mm) was significantly greater than that of the Synthes group (3.4 ± 1.8 mm; P < .01). DOE was caudal and distal in 79% of cases. CONCLUSIONS: Most tibial osteotomies were centered at a point distal and caudal to the intended osteotomy position. Use of a TPLO system with a saw guide was associated with more accurate placement of the osteotomy and more accurate leveling of the tibial plateau.

Surgical and nonsurgical treatment of peritoneopericardial diaphragmatic hernia in dogs and cats: 58 cases (1999-2008).

OBJECTIVE: To determine clinical findings and outcomes for cats and dogs with peritoneopericardial diaphragmatic hernia (PPDH) treated surgically or nonsurgically. DESIGN: Retrospective case series. ANIMALS: 28 dogs and 30 cats. PROCEDURES: Medical records for cats and dogs evaluated at 1 of 2 veterinary teaching hospitals were reviewed, and data regarding clinical signs, diagnostic and surgical findings, and outcome were evaluated. RESULTS: Prevalence of PPDH in the 2 hospitals during the study period was 0.025% (0.062% and 0.015% for cats and dogs, respectively); PPDH was an incidental finding for 13 (46.4%) dogs and 15 (50.0%) cats. Other congenital abnormalities were identified in 16 (571%) dogs and 7 (23.3%) cats (most commonly umbilical hernias, abdominal wall hernias cranial to the umbilicus, or sternal anomalies). Thirty-four (58.6%) animals underwent surgical repair of PPDH; 27 (79.4%) of these animals had a primary diagnosis of PPDH. Detection of clinical signs of PPDH (primary diagnosis) and intestines in the pericardial sac were significantly associated with surgical treatment. Short-term mortality rate for surgically treated animals was 8.8% (3/34). Clinical signs associated with PPDH resolved in 29 (85.3%) of surgically treated animals. No significant differences were detected between dogs and cats or between surgically and nonsurgically treated animals regarding long-term survival rate. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study indicated animals with clinical signs of PPDH were more likely to undergo surgery than were animals without such signs. Herniorrhaphy was typically effective for resolution of clinical signs. Long-term survival rates were similar regardless of treatment method. Surgical or nonsurgical treatment of PPDH may be appropriate for animals with or without clinical signs, respectively.

Fractures in regions of adaptive modeling and remodeling of central tarsal bones in racing Greyhounds.

OBJECTIVE: To evaluate and compare bone modeling and remodeling in fractured and non-fractured central tarsal bones (CTBs) of racing Greyhounds. SAMPLE: Paired cadaveric tarsi from 6 euthanized racing Greyhounds with right CTB fractures and 6 racing Greyhounds with other nontarsal injuries. PROCEDURES: CTBs were dissected and fractured CTBs were reconstructed. Central tarsal bones were evaluated through standard and nonscreen high-detail radiography, computed tomography, and histologic examination. The bone mineral density (BMD) was calculated adjacent to fracture planes and as a gradient on sagittal computed tomographic images. Sagittal and transverse plane sections of bone were obtained and submitted for subjective histologic assessment. Linear mixed-effects models were used to compare findings. RESULTS: Fractured right CTBs had greater BMD in the dorsal and midbody regions of the sagittal plane sections than did nonfractured CTBs. The BMD ratios from bone adjacent to the dorsal slab fracture planes were not different between fractured and nonfractured right CTBs. CONCLUSIONS AND CLINICAL RELEVANCE: Findings supported the existence of site-specific bone adaptation in CTBs of Greyhounds, with modeling and remodeling patterns that were unique to fractured right CTBs. The dorsal and midbody regions of fractured bones had greater BMD, and fractures occurred through these zones of increased BMD.

Risk factors for tibial tuberosity fracture after tibial plateau leveling osteotomy in dogs.

OBJECTIVE: To evaluate factors that predispose to tibial tuberosity (TT) fracture after tibial plateau leveling osteotomy (TPLO) in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=182) with cranial cruciate ligament (CCL) rupture undergoing 213 TPLO surgeries. METHODS: Medical records and radiographs of 2 groups of dogs that had TPLO surgery (2000-2001, 2004-2005) were evaluated to determine the effect of operative technique and surgeon experience on TT fracture. RESULTS: TT fracture was diagnosed in 8 dogs (9 TPLO, 4.2% of surgical procedures). Four fractures occurred after unilateral TPLO in 167 dogs (2.4%), 4 fractures occurred after simultaneous bilateral TPLO in 5 dogs (40%), and 1 fracture occurred after staged bilateral TPLO in 36 dogs (2.8%). Simultaneous bilateral TPLO resulted in a 12.4 times higher odds of TT fracture versus unilateral TPLO (P=.046). The mean absolute thickness of the TT after TPLO was less in dogs sustaining TT fractures (7.2 +/- 2.2 mm) than those that did not (10.8 +/- 2.7 mm, P<.0001). The odds of fracture decreased by 37% when the absolute TT width postosteotomy increased by 1 mm (P<.0001). An increase in tibial plateau angle at follow-up versus immediately postoperative was associated with TT fracture (P=.025). Surgeon experience was not associated with TT fracture. CONCLUSION: A combination of surgical decision-making and surgical technique play a role in the occurrence of TT fracture after TPLO. Simultaneous bilateral TPLO was associated with a high percentage of TT fracture. CLINICAL RELEVANCE: Careful planning of osteotomy positioning is advised while performing TPLO surgery.

Evaluation of pentosan polysulfate sodium in the postoperative recovery from cranial cruciate injury in dogs: a randomized, placebo-controlled clinical trial.

OBJECTIVE: To evaluate the efficacy of pentosan polysulfate (PPS) for improving the recovery period and mitigate the progression of osteoarthritis (OA) of the canine stifle after extracapsular stabilization of cranial cruciate ligament (CCL) injuries. STUDY DESIGN: Randomized, blinded, placebo-controlled clinical trial. ANIMALS: Dogs (n=40) with unilateral CCL instability. METHODS: Each dog had an extracapsular stabilization of the stifle with or without partial meniscectomy. Dogs were divided into 4 groups based on preoperative radiographic assessment and whether a partial meniscectomy was performed. Dogs were randomly assigned to either (3 mg/kg) PPS or placebo treatment in each group, and then injected subcutaneously weekly for 4 weeks. Lameness, radiographic changes, biological marker concentration in blood and urine, and ground reaction forces (GRFs) were collected preoperatively, and at 6, 12, 24, and 48 weeks. Data were analyzed within and between groups using repeated measures ANOVA; P<.05 was considered significant. RESULTS: No adverse reactions to PPS were reported. Thirty-nine dogs completed a minimum of 24-weeks follow-up and 33 dogs completed 48 weeks. All dogs clinically improved after surgery without differences in lameness score, vertical GRFs, or radiographic progression. Grouped and evaluated only by initial radiographic score, PPS-treated dogs improved significantly faster in braking GRFs than placebo-treated dogs. In dogs with partial meniscectomies, urine deoxypyridinoline, and serum carboxy-propeptide of type II collagen were significantly increased at 6 weeks in placebo-treated dogs compared with PPS-treated dogs. CONCLUSIONS: PPS administered after stabilization of the cruciate deficient stifle may prove to be a useful adjunctive treatment option, although further studies are necessary to substantiate this claim.

Evaluation of a pressure walkway system for measurement of vertical limb forces in clinically normal dogs.

OBJECTIVE: To compare ground reaction forces (GRFs) measured by use of a pressure-sensitive walk-way (PSW) and a force plate (FP) and evaluate weekly variation in the GRFs and static vertical forces in dogs. ANIMALS: 34 clinically normal dogs and 5 research dogs with lameness. PROCEDURE: GRF data were collected from 5 lame and 14 clinically normal dogs by use of an FP and a PSW. Peak vertical force (PVF), vertical impulse (VI), and velocity measurements (determined by use of photocells and PSW data) were compared between groups. Peak vertical force, VI, stride length, ground phase time (ie, contact time), and static body weight distribution data were collected on 2 occasions, 1 week apart, in 20 different clinically normal dogs by use of a PSW; week-to-week variation in values was evaluated. RESULTS: Measurements of velocity derived by use of the photocells were not different from those derived by use of the PSW. For any 1 limb, values derived by use of the PSW were significantly lower than values derived with the FP. For values obtained by use of either technique, there were no differences between left and right limbs except for values of PVF measured via PSW in forelimbs. Values of PVF, VI, contact time, stride length, and static weight distribution generated by the PSW did not vary from week to week. CONCLUSIONS AND CLINICAL RELEVANCE: Values for GRFs varied between the FP and PSW. However, data derived by use of PSW were consistent and could be used to evaluate kinetic variables over time in the same dog.

The coxib NSAIDs: potential clinical and pharmacologic importance in veterinary medicine.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are used to control acute and chronic pain as well as to manage oncologic and neurologic diseases in human and veterinary patients. Despite ongoing research and efforts to improve the safety and efficacy of existing drugs, adverse effects such as gastrointestinal irritation, renal and hepatic toxicity, interference with hemostasis, and reproductive problems persist. The true incidence of NSAID-induced adverse effects in animals is unknown, but is likely underestimated, because cats and dogs may be more sensitive than humans to NSAIDs due to alterations in drug metabolism, absorption, and enterohepatic recirculation. NSAIDs produce both analgesia and toxic adverse effects primarily by inhibiting cyclooxygenase (COX), thereby decreasing the production of prostaglandins that signal inflammation and pain as well as mediate physiologic functions such as platelet aggregation, gastric protection, and electrolyte balance in the kidney. The presence of at least 2 COX isoforms may account for variability in NSAID efficacy and toxicity both within and among species. This paper reviews and evaluates the published literature on the safety, pharmacology, uses, and complications of a subclass of COX-1-sparing drugs, the coxibs, in veterinary medicine. Coxibs and other COX-1-sparing drugs provide a clinically useful improvement over traditional NSAIDs, but data are incomplete and more in vivo species-specific, target-tissue, and clinical studies are needed.

Femoral bone adaptation to stable long-term cemented total hip arthroplasty in dogs.

OBJECTIVE: To quantify long-term bone adaptation after stable cemented total hip arthroplasty (cTHA) in dogs. STUDY DESIGN: Clinical study. ANIMALS: Fourteen dogs. METHODS: Femoral specimens were collected from client-owned dogs that were donated after death because of causes unrelated to their cTHA. Mean (+/-SEM) dog age was 11.4+/-0.7 years and implant duration was 5.3+/-0.7 years. Implant stability was established from radiographic signs and gross mechanical stability. Femurs were evaluated at 3 levels based on implant length: proximal stem (PS), mid-stem (MS), and distal to stem (DS). Cortical area, medullary area, and porosity were measured at each level. Implanted femurs were compared to contralateral nonimplanted femurs. RESULTS: Cortical area and cortical porosity were significantly increased in implanted femurs compared to nonimplanted femurs. Cortical area was increased at the MS and DS levels, and porosity was increased at the PS and MS levels in implanted femurs. Porosity was greatest in the endosteal region at the PS and MS levels in implanted femurs. CONCLUSIONS: Significant differences in femoral geometry and cortical porosity were detected after long-term stable cTHA. Net bone loss proximally and increased bone mass distally support stress shielding as a important mechanical factor associated with bone adaptation. Distribution of porosity shifts to endosteal regions after long-term cTHA. CLINICAL RELEVANCE: Significant site-specific femoral adaptation occurs in response to stable cTHA and may precede implant loosening.

Femoral bone adaptation to unstable long-term cemented total hip arthroplasty in dogs.

OBJECTIVE: To evaluate femoral adaptation after unstable long-term cemented total hip arthroplasty (cTHA) in dogs. STUDY DESIGN: Clinical study. ANIMALS: Four dogs. METHODS: Paired femurs were examined from client-owned dogs that were donated to a retrieval program after death from causes unrelated to their cTHA. Mean (+/-SEM) dog age was 10.0+/-1.5 years and implant duration was 6.0+/-1.4 years. Implanted femurs had radiographic changes associated with implant loosening and gross mechanical instability at femur retrieval. Femurs were evaluated at 3 levels relative to implant length. Cortical area and medullary area were measured at each level, and cortical porosity was assessed at each level in 4 quadrants and in 3 regions. Implanted femurs were compared with the contralateral non-implanted femurs. RESULTS: Cortical area and cortical porosity were increased at all levels in femurs with unstable implants. Implanted femurs had increased porosity in all quadrants and regions at the proximal 2 levels, and increased porosity in only the cranial quadrant and mid-cortical area at the distal level, when compared with contralateral non-implanted femurs. Corresponding medullary areas were not different. CONCLUSIONS: Significant histomorphometric changes occur in femurs after unstable cTHA. The patterns of periosteal bone formation and endosteal bone resorption support mechanisms of stress shielding and wear debris-mediated osteolysis as factors that may contribute to femoral adaptation and implant loosening. CLINICAL RELEVANCE: Despite popularity and excellent return to function with cTHA, aseptic loosening remains a serious long-term complication. Substantial net bone loss and unfavorable environment with unstable cTHA may make revision surgery less successful.

Orthogonal view analysis for evaluating the femoral component position of total hip implants in dogs using postoperative radiographs.

OBJECTIVE: To show the ability to obtain repeatable, accurate, quantitative data to assess the position of the femoral component of canine total hip implants using postoperative radiographs. STUDY DESIGN: Cadaveric study and clinical trial. ANIMALS: Five cadaveric canine femurs and 4 patients. METHODS: Femoral implants were placed into 5 cadaveric canine femurs in predetermined locations. Orthogonal radiographs were taken of each femur at 10 degrees intervals as they were moved through a natural range of hip motion. An assessment of implant position was made with each set of radiographs and analyzed to observe significant inconsistencies in the values obtained when the femur was repositioned. Three investigators positioned and radiographed the hips of 4 client-owned dogs that had total hip arthroplasty (THA). Each investigator obtained a set of orthogonal radiographic views from which implant position was measured. The measurements obtained from each investigator's set of radiographs were statistically analyzed to evaluate for interobserver differences. RESULTS: The methods described indicate that consistent data regarding femoral implant placement can be obtained from postoperative radiographs of THA patients. Under most circumstances, change in position of the femur did not significantly affect femoral implant measurements. There were no significant differences noted among values obtained by different investigators. CONCLUSIONS: Measurements based on the femoral and implant axes obtained from orthogonal radiographic views of the femur provide a means for obtaining accurate and consistent quantitative data regarding femoral implant position using postoperative radiographs of canine THA patients. CLINICAL RELEVANCE: Acquisition of quantitative information about femoral implant position using postoperative radiographs will facilitate development of a readily available data source. This information, attainable in a clinical setting, may help identify elements of implant position that are important in determining the clinical outcome of THA in dogs.