Morphologic impact of four surgical techniques to correct excessive tibial plateau angle in dogs: A theoretical radiographic analysis.

OBJECTIVE: To determine morphologic differences between four tibial osteotomy techniques used to correct excessive tibial plateau angle (eTPA). STUDY DESIGN: Retrospective radiographic analysis. SAMPLE POPULATION: Sixteen dogs (27 tibias) with eTPA. METHODS: Virtual corrections of eTPA were performed on sagittal plane radiographs of canine tibia using four tibial osteotomy techniques and categorized into respective groups. Group A represented the center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) and coplanar cranial closing wedge ostectomy (CCWO), Group B the tibial plateau leveling osteotomy (TPLO) and CCWO, Group C the modified CCWO (mCCWO), and Group D the proximal tibial neutral wedge osteotomy (PTNWO). Pre- and post-correction TPA, tibial length and mechanical cranial distal tibial angle (mCrDTA) were measured and compared. RESULTS: Mean TPA prior to correction was 42.67 ± 6.1°. Post-correction mean TPAs were 10.47 ± 2.1°, 6.77 ± 1.6°, 4.76 ± 1.5°, and 7.09 ± 1.3° for Groups A, B, C, and D, respectively. TPA correction accuracy in Groups A and D varied least from target TPAs. Tibial shortening was documented in Group B in contrast to other groups. The greatest mechanical axis shift was identified in Group A. CONCLUSION: Each technique achieved TPA < 14° despite having different effects on tibial morphology including alteration of tibial length, mechanical axis shift and variation in correctional accuracy. CLINICAL SIGNIFICANCE: Despite all methods being able to correct eTPA, the choice of technique will affect morphology in unique ways and should be considered prior to surgery to consider the implications in a given patient.

Comparison of two postoperative complication grading systems after treatment of stifle and shoulder instability in 68 dogs.

OBJECTIVE: (1) To adapt and apply the Clavien-Dindo (aCD) postoperative complication grading system to dogs experiencing complications following a single orthopedic procedure. (2) To compare the reliability of the Clavien-Dindo system to the Cook complication grading system. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Sixty-eight client-owned dogs. METHODS: Scenarios derived from complications following TightRope stabilization of the stifle and shoulder were graded by four ACVS-boarded surgeons using two systems; the Cook 3-point scale and the aCD 5-point scale. Because the aCD system distinguishes complications from outcomes ("sequelae" or "failure to cure"), two data sets were created: one with (n = 76) and without (n = 67) inclusion of "sequelae" and "failure to cure" cases. Interobserver reliability was evaluated using intraclass correlation coefficient (ICC) calculations. RESULTS: Seventy-six scenarios from 68 records were evaluated. The ICC of the aCD system was 0.620 consistent with moderate reliability. The reliability of the Cook system was good, with an ICC of 0.848. Exclusion of cases with "sequelae" or "failure to cure" resulted in excellent reliability of the aCD system (ICC = 0.975) and good reliability of the Cook systems (ICC = 0.857). CONCLUSION: The aCD grading system was less reliable than the Cook system when evaluating all cases but more reliable when evaluating cases of complications excluding "sequelae" and "failures to cure". CLINICAL SIGNIFICANCE: The Cook grading system is reliably good in grading postoperative complications in dogs. The aCD system can also be used to assess postoperative complications with excellent reliability but is less reliable when distinguishing complications from other postoperative outcomes.

Radiographic determination of normal canine femoral alignment in the sagittal plane: A cadaveric pilot study.

OBJECTIVE: To establish a reliable methodology for radiographic determination of alignment of the normal canine femur in the sagittal plane. STUDY DESIGN: Cadaveric pilot study. SAMPLE POPULATION: Twenty-nine cadaveric canine femurs. METHODS: Femoral specimens were collected from the University of Missouri veterinary anatomy laboratory, and standardized sagittal plane radiographs were obtained. The anatomic and mechanical axes, joint orientation, lines and joint orientation angles were determined in the sagittal plane by using the center of rotation of angulation methodology. Landmarks were clearly described to allow repeatability and reliability of measurements. Three observers with various degrees of experience measured two centers of rotation of normal angulation, the anatomic caudoproximal femoral angle, and the mechanical caudodistal femoral angle for all femurs on three separate days. Interobserver and intraobserver reliability were measured by using two-way mixed intraclass correlation coefficients (ICC) with associated 95% CI. RESULTS: Twenty-nine medium to large breed canine femora were measured. A high degree of correlation was present both among and between observers for all measurements performed, as defined by an ICC >0.8 for each. CONCLUSION: The described methodology was reliable and repeatable for measurement of angulation of grossly normal canine femora in the sagittal plane when performed by observers with varying degrees of clinical experience, as evidenced by a high degree of correlation for all values measured. CLINICAL SIGNIFICANCE: This methodology may be used for standardized evaluation of alignment of canine femora in the sagittal plane.

Coxofemoral Joint Luxation in Dogs Treated with Toggle Rod Stabilization: A Multi-Institutional Retrospective Review with Client Survey.

Coxofemoral luxation is the most common type of joint luxation observed clinically in dogs. This retrospective study determines the complications and outcomes of open reduction and internal fixation of coxofemoral luxations using a toggle rod stabilization in 58 dogs. The purpose of the study was to compare the results with previous studies to ascertain commonalities and differences. A majority of the canine luxations were stabilized using a 4.0 or 3.2 mm commercial toggle rod and either one or two strands of OrthoFiber, FiberWire, or monofilament nylon suture. Postoperative complications developed in 25 of the 58 (43%) dogs, with major complications in 9 cases (15.5%). The most common major complication was reluxation, which occurred in 6 dogs (10%). Five of the 6 cases of reluxation received monofilament suture, although there was not a statistically significant relationship between suture type and reluxation. Owner responses to a questionnaire reported good to excellent results for satisfaction with the procedure in 90% of cases. Results of the present study suggest that toggle rod stabilization remains an effective method for the treatment of coxofemoral joint luxation in dogs.

Low-Level Laser Therapy for Osteoarthritis Treatment in Dogs at Missouri Veterinary Practice.

A qualitative survey was electronically distributed to practicing veterinarians in the state of Missouri to evaluate the frequency of use and economic impact of low-level laser therapy (LLLT) for the treatment of osteoarthritis (OA) in dogs in Missouri. The survey response rate was 10% (89/867). Approximately half (43%) of respondents had LLLT units, of which all used LLLT for OA treatment in dogs. In respondents without LLLT units, 20% referred patients for LLLT OA treatment. Training was most often obtained in-house by a representative of the LLLT unit manufacturer (76%). Treatment dose was largely unknown and chosen by predetermined settings on the LLLT unit (65%). In the majority of patients (84%), no treatment site preparation was performed. An average of four patients with OA were treated per wk with an average cost per treated joint of $28 (range: $15-45). This study provides insight into the current clinical use and estimated annual economic impact ($6.2 million per year) of treating a single OA joint in dogs with LLLT by Missouri veterinarians. The frequency with which LLLT is used in the treatment of OA combined with the variation in training and treatment protocols supports the need for further research regarding the application and efficacy of LLLT in dogs with OA.

Classification of Angular Limb Deformities Affecting the Canine Radius and Ulna Using the Center of Rotation of Angulation Method.

OBJECTIVE: To classify the type of angular deformity affecting the radius and ulna in canine limbs using the center of rotation of angulation methodology. STUDY DESIGN: Retrospective case series. ANIMALS: Dogs (n=71) diagnosed with thoracic limb lameness attributable to antebrachial angular limb deformities. METHODS: Medical records from 2006-2013 were searched and cases with orthogonal radiographs or computed tomographic scans of the affected antebrachium were included. Classification of the deformity in the frontal plane and the presence of sagittal plane angulation, torsion, and adjacent joint radiographic disease were determined and compared. RESULTS: Chondrodystrophic (n=26; 44 limbs) and non-chondrodystrophic (n=45; 62 limbs) dogs were included. Thirty-five uniapical and 71 biapical or multiapical deformities in the frontal plane were identified. The incidence of biapical deformities was statistically higher in chondrodystrophic compared to non-chondrodystrophic dogs (P=.02). When breeds were combined, biapical deformities were associated with a significantly higher incidence of adjacent radiographic joint disease (P=.049), more frequently affecting the elbow (P=.022). Overall, 82% of the 106 limbs had radiographic evidence of either elbow or carpal joint disease at the time of presentation. CONCLUSION: Biapical deformities are common in dogs with limb deformities, particularly chondrodystrophic dogs. Radiographic evidence of disease in adjacent joints should be evaluated in patients presenting for antebrachial deformities.

The Effect of Sliding Humeral Osteotomy (SHO) on Frontal Plane Thoracic Limb Alignment: An Ex Vivo Canine Cadaveric Study.

OBJECTIVE: To determine the effect of sliding humeral osteotomy (SHO) on frontal plane thoracic limb alignment in standing and recumbent limb positions. STUDY DESIGN: Canine cadaveric study. SAMPLE POPULATION: Canine thoracic limbs (n=15 limb pairs). METHODS: Limbs acquired from healthy Labrador Retrievers euthanatized for reasons unrelated to this study were mounted in a limb press and aligned in a standing position followed by axial loading at 30% body weight. Frontal plane radiography was performed in standing and recumbent positions pre- and post-SHO. In the standing position, lateralization of the foot was measured pre- and post-SHO using a textured grid secured to the limb press base plate. Twelve thoracic limb alignment values (mean ± SD and 95% CI) were determined using the center of rotation of angulation (CORA) method were compared using linear mixed models to determine if significant differences existed between limb alignment values pre- or post-SHO, controlling for dog, limb, and limb position. RESULTS: Six of 12 standing or recumbent alignment values were significantly different pre- and post-SHO. SHO resulted in decreased mechanical lateral distal humeral angle and movement of the mechanical humeral radio-ulnar angle, radio-ulnar metacarpal angle, thoracic humeral angle, and elbow mechanical axis deviation toward coaxial limb alignment. In the standing position, the foot underwent significant lateralization post-SHO. CONCLUSION: SHO resulted in significant alteration in frontal plane thoracic limb alignment. Additional studies are necessary to determine if the changes reported using our ex vivo model occur following SHO in vivo.

Comparison of Short-Term Postoperative Analgesia by Epidural, Femoral Nerve Block, or Combination Femoral and Sciatic Nerve Block in Dogs Undergoing Tibial Plateau Leveling Osteotomy.

OBJECTIVE: To compare early postoperative analgesia in dogs undergoing unilateral tibial plateau leveling osteotomy (TPLO) that received bupivacaine via preoperative femoral nerve block (FNB), combination femoral-sciatic nerve block (F+SNB), or lumbosacral epidural (EPI). STUDY DESIGN: Randomized, blinded, prospective clinical trial. ANIMALS: Forty-five client-owned dogs undergoing unilateral TPLO. METHODS: Dogs undergoing unilateral TPLO were enrolled and randomly allocated to 1 of 3 treatments: FNB, F+SNB, or EPI. Assessments were completed by an observer blinded to treatment at 0, 1, 2, 4, 6, and 8 hours after extubation using the Glasgow Composite Pain Score-Short Form (GCPS-SF). Dogs with a total score ≥ 6 or ≥ 3 in any category were given a rescue analgesic. Outcome measures analyzed for differences across treatments were the GCPS-SF at each time point, time to first rescue analgesic, and total number of rescue analgesic doses per dog. RESULTS: The GCPS-SF score at extubation was significantly higher for FNB (median 3) compared to F+SNB (median 2). A significantly higher proportion of dogs receiving FNB (4/14) than F+SNB (0/17) required rescue analgesic at extubation. There was no significant difference in the proportion of dogs requiring rescue at extubation between FNB and EPI (2/14) or between F+SNB and EPI. There was no significant difference in the median time to first rescue between FNB (0 hours) and F+SNB (2 hours) or between F+SNB and EPI (1.5 hours). CONCLUSION: In dogs undergoing unilateral TPLO, bupivacaine administered via FNB, alone or in combination with sciatic nerve block, can provide short-term postoperative analgesia not different to that with administration via lumbosacral epidural.

Determination of the mechanical axis and joint orientation lines in the canine humerus: a radiographic cadaveric study.

OBJECTIVE: To describe a radiographic method for determination of the mechanical axes and joint orientation lines in orthogonal planes for the canine humerus and establish a range of normal joint orientation angles in a population of large breed dogs. STUDY DESIGN: Radiographic study. SAMPLE POPULATION: Humeri (n = 50) of skeletally mature, nonchondrodystrophic canine cadavers, weighing 20-40 kg with no evidence of orthopedic disease. METHODS: Mediolateral and craniocaudal digital radiographs were used to establish anatomic landmarks for determination of the mechanical axis in both frontal and sagittal planes, the joint orientation lines of both shoulder and elbow and measurement of the resulting mechanical lateral distal humeral angle (mLDHA) in the frontal plane, and the mechanical caudal proximal humeral angle (mCaPHA), and mechanical cranial distal humeral angle (mCrDHA) in the sagittal plane. RESULTS: Means (± SD) for the joint orientation angles were: mLDHA, 86.92 ± 1.24°, mCaPHA, 43.28 ± 5.44°, and mCrDHA, 71.86 ± 3.97°. The 95% CI ranges for the joint orientation angles were mLDHA, 86.58-87.86°, mCaPHA, 41.77-44.79°, and mCrDHA, 70.76°-72.96°. CONCLUSION: A method for measurement of the mechanical axis and associated joint angles of the normal canine humerus in the frontal and sagittal planes was established and reference intervals reported. In the frontal plane, it was determined that the canine humerus is not perpendicular to the elbow joint; therefore, elbow mechanical axis deviation is normal and requires further assessment.

Thoracic limb alignment in healthy labrador retrievers: evaluation of standing versus recumbent frontal plane radiography.

OBJECTIVE: To report thoracic limb alignment values in healthy dogs; to determine if limb alignment values are significantly different when obtained from standing versus recumbent radiographic projections. STUDY DESIGN: Prospective cross-sectional study. ANIMALS: Labrador Retrievers (n = 45) >15 months of age. METHODS: Standing and recumbent radiographs were obtained and limb montages were randomized before analysis by a single investigator blinded to dog, limb, and limb position. Twelve limb alignment values were determined using the CORA methodology. Measurements were performed in triplicate and intra-observer variability was evaluated by intra-class correlation coefficient (ICC). Limb alignment values were reported as mean ± SD and 95% confidence intervals. Linear mixed models were used to determine if significant associations existed between limb alignment values and limb, limb position, gender, age, weight, and body condition score. RESULTS: There were significant differences in standing and recumbent limb alignment values for all values except elbow mechanical axis deviation (eMAD). Limb, gender, age, body weight, and body condition score had no effect. ICC values ranged from 0.522 to 0.758, indicating moderate to substantial agreement for repeated measurements by a single investigator. CONCLUSIONS: Limb alignment values are significantly different when determined from standing versus recumbent radiographs in healthy Labrador Retrievers.

A non-spherical core in the explosion of supernova SN 2004dj.

An important and perhaps critical clue to the mechanism driving the explosion of massive stars as supernovae is provided by the accumulating evidence for asymmetry in the explosion. Indirect evidence comes from high pulsar velocities, associations of supernovae with long-soft gamma-ray bursts, and asymmetries in late-time emission-line profiles. Spectropolarimetry provides a direct probe of young supernova geometry, with higher polarization generally indicating a greater departure from spherical symmetry. Large polarizations have been measured for 'stripped-envelope' (that is, type Ic; ref. 7) supernovae, which confirms their non-spherical morphology; but the explosions of massive stars with intact hydrogen envelopes (type II-P supernovae) have shown only weak polarizations at the early times observed. Here we report multi-epoch spectropolarimetry of a classic type II-P supernova that reveals the abrupt appearance of significant polarization when the inner core is first exposed in the thinning ejecta (approximately 90 days after explosion). We infer a departure from spherical symmetry of at least 30 per cent for the inner ejecta. Combined with earlier results, this suggests that a strongly non-spherical explosion may be a generic feature of core-collapse supernovae of all types, where the asphericity in type II-P supernovae is cloaked at early times by the massive, opaque, hydrogen envelope.

Measurement of femoral and tibial joint reference angles and pelvic limb alignment in cats.

OBJECTIVE: To report pelvic limb joint reference angles, limb alignment, and mechanical axis deviation for the feline pelvic limb. STUDY DESIGN: Cadaveric radiographic anatomic study. ANIMALS: Skeletally mature, mixed breed cats (n = 50). METHODS: Extended pelvic limb radiography was performed and images analyzed to determine femoral anatomic joint reference angles, femoral and tibial mechanical joint reference angles, tibiofemoral angle, metatarsotibial angle, mechanical axis-femur and mechanical axis-metatarsus angles, and mechanical axis deviation of the stifle and tarsus. Mean ± SD and 95% confidence intervals (95% CI) were calculated. RESULTS: Mean ± SD angles and 95% CI were: anatomic lateral proximal femoral (103.9° ± 3.8°; 103.1° - 104.6°), anatomic lateral distal femoral (93.8° ± 2.5°; 93.3° - 94.3°), mechanical lateral proximal femoral (100.5° ± 3.7°; 99.8° - 101.2°), mechanical lateral distal femoral (97.2° ± 2.2°; 96.7° - 97.6°), mechanical medial proximal tibial (88.0° ± 3.2°; 87.3° - 88.6°), mechanical medial distal tibial (107.6° ± 4.8°; 106.6° - 108.5°), mechanical tibiofemoral (7.4° varus ± 2.5°; 6.9° - 7.9°), mechanical metatarsotibial (6.0° valgus ± 3.5°; 5.3° - 6.7°); mechanical axis-femur (3.2° ± 1.4°; 2.9° - 3.5°) and mechanical axis-metatarsus (2.4° ± 2.0°; 1.7° - 2.1°). Mechanical axis deviation of the stifle and of the tarsus were 2.0% ± 0.9% (95% CI: 1.9-2.2) and 0.8% ± 1.0% (95% CI: 0.7-1.0), respectively. CONCLUSIONS: Mean pelvic limb joint reference and limb alignment angles can be used for diagnosing angular limb deformities of the feline pelvic limb and for planning corrective osteotomies in affected cats.

Cell-based meniscal tissue engineering: a case for synoviocytes.

BACKGROUND: Avascular meniscal injuries are largely incapable of healing; the most common treatment remains partial meniscectomy despite the risk of subsequent osteoarthritis. Meniscal responses to injury are partially mediated through synovial activity and strategies have been investigated to encourage healing through stimulating or transplanting adjacent synovial lining. However, with their potential for chondrogenesis, synovial fibroblast-like stem cells hold promise for meniscal cartilage tissue engineering. QUESTIONS/PURPOSES: Thus, specific purposes of this review were to (1) examine how the synovial intima and synoviomeniscal junction affect current meniscal treatment modalities; and (2) examine the components of tissue engineering (cells, scaffolds, bioactive agents, and bioreactors) in the specific context of how cells of synovial origin may be used for meniscal healing or regeneration. METHODS: An online bibliographic search through PubMed was performed in March 2010. Studies were subjectively evaluated and reviewed if they addressed the question posed. Fifty-four resources were initially retrieved, which offered information on the chondrogenic potential of synovial-based cells that could prove valuable for meniscal fibrocartilage engineering. RESULTS: Based on the positive effects of adjoining synovium on meniscal healing as used in some current treatment modalities, the chondrogenic potential of fibroblast-like stem cells of synovial origin make this cell source a promising candidate for cell-based tissue engineering strategies. CONCLUSIONS: The abundance of autologous synovial lining, its ability to regenerate, and the potential of synovial-derived stem cells to produce a wide spectrum of chondral matrix components make it an ideal candidate for future meniscal engineering investigations.

Evaluation of in vitro growth factor treatments on fibrochondrogenesis by synovial membrane cells from osteoarthritic and nonosteoarthritic joints of dogs.

OBJECTIVE: To determine the in vitro effects of selected growth factors on fibrochondrogenesis by synovial membrane cells from nonosteoarthritic (normal) and osteoarthritic joints of dogs. ANIMALS: 5 dogs with secondary osteoarthritis of shoulder or stifle joints and 6 dogs with normal joints. PROCEDURES: Synovial membrane cells were harvested from normal and osteoarthritic joints and cultured in monolayer with or without (control) basic fibroblast growth factor, transforming growth factor-ß1, and insulin-like growth factor-1. In the cultured cells, fibrochondrogenesis was measured by use of a real-time reverse transcriptase PCR assay to determine relative expressions of collagen I, collagen II, and aggrecan genes and of 3 genes involved in embryonic chondrogenesis: Sry-type homeobox protein-9 (SOX-9), frizzled-motif associated with bone development (Frzb), and regulator of G-protein signaling-10 (RGS-10). Tissue collagen content was measured via a hydroxyproline assay, and sulfated glycosaminoglycan content was measured via a 1,9-dimethylmethylene blue assay. Cellularity was determined via a double-stranded DNA assay. Immunohistochemical analysis for collagens I and II was also performed. RESULTS: In vitro collagen synthesis was enhanced by growth factor stimulation. Although osteoarthritic-joint synoviocytes could undergo a fibrocartilage-like phenotypic shift, their production of collagenous extracellular matrix was less than that of normal-joint synoviocytes. Gene expressions of SOX-9 and RGS-10 were highest in the osteoarthritic-joint cells; Frzb expression was highest in growth factor treated cells. CONCLUSIONS AND CLINICAL RELEVANCE: Autogenous synovium may be a viable cell source for meniscal tissue engineering. Gene expressions of SOX-9 and RGS-10 may be potential future targets for in vitro enhancement of chondrogenesis.

Acetabular ventroversion with double pelvic osteotomy versus triple pelvic osteotomy: a cadaveric study in dogs.

OBJECTIVE: To determine which of 3 different plate angles (20°, 25°, 30°) used in double pelvic osteotomy (DPO) would result in the most similar acetabular angle (AA) achieved with a 20° triple pelvic osteotomy (TPO) technique in dogs. STUDY DESIGN: Experimental anatomic study. ANIMALS: Cadaveric canine pelves (n = 8). METHODS: Transverse plane computed tomographic images of cadaveric pelves with intact sacroiliac joints, mounted in a custom jig, were made (baseline) and again after DPO (20°, 25°, 30°) and TPO (20°) and pelvic angles measured in 6 transverse planes. Pelvic angles of the 3 DPO techniques were compared with TPO using concordance correlation to determine which DPO angle resulted in an acetabular ventroversion angle closest to TPO. RESULTS: Mean ± SD AAs were 32.89 ± 2.23 (baseline), 47.39 ± 4.39 (20° DPO), 51.43 ± 5.06 (25° DPO), 54.75 ± 4.38 (30° DPO), and 50.20 ± 5.76 (20° TPO). Concordance correlations for the AA compared with 20° TPO were 0.027 (baseline), 0.721 (20° DPO), 0.902 (25° DPO), and 0.593 (30° DPO). A concordance correlation of ≥ 0.8 indicates good correlation. CONCLUSIONS: A 25° DPO is most similar in acetabular ventroversion to 20° TPO (concordance correlation, 0.902).

Physeal Injuries and Angular Limb Deformities.

Physeal injuries are common in the developing small animal and can result in growth disturbances of the forelimb. Resulting deformities can include limb shortening, joint incongruity, angulation, and alterations in joint loading with subsequent osteoarthritis, remodeling, and debilitation. Because of the unique paired bone configuration, the antebrachium is the main source for malalignment resulting from physeal disturbance in the forelimb. Successful correction of deformities requires in-depth understanding of normal physeal activity; careful consideration of patient signalment; and the ability to quantify the location, magnitude, and plane of the deformity or deformities.

Skeletal Manifestations of Heritable Disproportionate Dwarfism in Cats as Determined by Radiography and Magnetic Resonance Imaging.

OBJECTIVE: The aim of this study was to characterize the radiographic alignment of thoracic and pelvic limbs and evaluate for intervertebral disc disease in cats with feline disproportionate dwarfism (FDD). STUDY DESIGN: Observational cross-sectional study. Radiographic joint orientation angles were measured in 10 thoracic and pelvic limbs from 5 FDD cats and compared with those angles measured in 24 thoracic limbs and 100 pelvic limbs from skeletally normal cats. Magnetic resonance imaging of the spine was performed in 2 FDD cats for the evaluation of pathology of the intervertebral discs or vertebrae. RESULTS: All limbs from FDD cats possessed deformities. FDD humeri demonstrated procurvatum proximally, and recurvatum distally in the sagittal plane, but showed no difference in the frontal plane. FDD radii possessed excessive recurvatum proximally, and procurvatum distally in the sagittal plane, and varus proximally and valgus distally in the frontal plane. Whereas no torsion was discernible in the humeri, all radii had external torsion. In the frontal plane, FDD femurs exhibited varus both proximally and distally whereas the tibia possessed proximal valgus and distal varus. No torsion in the pelvic limbs was observed. No spinal pathology was detected in the FDD cats included in the original study. CONCLUSION: Feline disproportionate dwarfism results in significant appendicular deformity in all limbs. The incidence of intervertebral disc degeneration in FDD cats is inconclusive.

Surgical management of orbital nodular granulomatous episcleritis in a dog.

A 27 kg, 6-year-old, male castrated German shorthaired pointer presented to the University of Missouri, Veterinary Teaching Hospital with the complaint of progressive exophthalmia of 2 years duration optical density (OD). Lack of retropulsion OD was noted on physical examination. Anterior segment examination OU and fundic examination OS did not reveal any abnormalities. Examination of the fundus OD revealed focal scleral indentation of the inferior nasal globe. The indentation changed location with globe movement OD. MRI and CT scan revealed a well-circumscribed, approximately 2 cm in diameter mass located caudal and ventral to the affected globe that appeared to communicate with the nictitating membrane with absence of any bony involvement. A modified lateral orbitotomy was recommended and performed to remove the orbital mass and nictitating membrane en-bloc. Histopathology and immunohistochemistry of the mass confirmed a diagnosis of nodular granulomatous episcleritis (NGE). Postoperatively, the dog developed absolute keratoconjunctivitis sicca (KCS). Examples of primary episcleral inflammation in the dog include diffuse episcleritis, NGE, nodular fasciitis, fibrous histiocytoma, proliferative conjunctivitis/keratoconjunctivitis, pseudotumor, and Collie granuloma. The etiology of these episcleral inflammations is presumed to be immune mediated. To our knowledge, this is the first report of NGE affecting the orbital region of a dog. Development of absolute KCS resulting from excision of the nictitating membrane is also supported by this case.

Detection and evaluation of matrix metalloproteinases involved in cruciate ligament disease in dogs using multiplex bead technology.

OBJECTIVE: To measure matrix metalloproteinases (MMPs) suspected to be involved in the initiation or progression of osteoarthritis (OA) in cranial cruciate ligament (CCL) explant culture media using multiplex bead technology. STUDY DESIGN: In vitro experimental study. ANIMALS: Adult dogs with (n=10) and without (n=10) CCL deficiency. METHODS: Based on clinical, radiographic, and gross evidence of CCL deficiency, excised CCL were classified as normal and intact (n=10) or partially torn (n=10). The ligament was excised and immediately placed in tissue culture. Culture media were sampled and replaced on days 3 and 6. MMP-1, 2, 3, 9, and 13 were quantified in explant media using a multiplexing machine that uses flow cytometry, microspheres, spectral dyes, lasers, digital signal processing, and traditional chemistry. MMP concentrations were determined using a standard curve constructed from the serial dilution of positive controls. Media MMP concentrations comparing the type of ligament and the time frame were analyzed using a Mann-Whitney rank sum test. RESULTS: Media exposed to intact ligaments had >3 times the amount of MMP-2 than for partially torn ligaments on day 6 (P=.006). Media exposed to intact ligaments also had significantly higher levels of MMP-3 than for partially torn ligaments on day 3 (P=.035) and on day 6 (P=.05). CONCLUSIONS: MMP multiplexing is a reliable, cost-effective, efficient, and sample-sparing method of MMP quantification. MMP-2, 3, 9, and 13 are released from CCL explants exposed to culture media and can be detected using multiplex bead technology. CLINICAL RELEVANCE: CCL remnants exposed to the intra-articular environment may release degradative enzymes in vivo similar to that demonstrated in this in vitro study. Because MMPs are known to be involved in the initiation and progression of OA, debridement of these remnants as a component of treatment for cruciate disease in dogs deserves consideration.

The effect of uniaxial cyclic tensile load on gene expression in canine cranial cruciate ligamentocytes.

OBJECTIVE: To determine the effects of uniaxial cyclic tensile load amplitude and duration on gene expression in cranial cruciate ligamentocytes cultured in monolayer. STUDY DESIGN: In vitro experimental study. ANIMALS: Adult dogs (n=9) weighing 20-35 kg. METHODS: Cranial cruciate ligaments (CCL, n=18) were aseptically collected, diced, digested using clostridial collagenase, and primary monolayer cultures were established. CCL cells were seeded at a concentration of 3 x 10(5) cells/mL onto a specialized collagen membrane. After 24 hours to allow attachment, ligamentocytes were subjected to 0%, 4%, or 8% uniaxial strain for 24 or 48 hours using a sinusoidal strain profile at 0.5 Hz. At the end of each time point, the ligamentocytes were harvested and analyzed for collagen 1 (COL1), collagen 3 (COL3), and matrix metalloproteinase-3 (MMP-3) gene expression using reverse transcriptase real-time polymerase chain reaction. RESULTS: Approximately 33% of CCL processed for this study yielded viable cell cultures compared with 100% of the medial collateral ligaments processed. For CCL cells under uniaxial strain, gene expression for COL1 was variable, but higher strains and longer time in culture resulted in increased COL1 expression. There were no significant differences found for COL3 at any time point or between strain regimens. In general, MMP-3 gene expression was increased early in tissue culture and at higher strains. CONCLUSIONS: COL1 and MMP-3 gene expression can be influenced by amplitude and duration of strain on CCL cells in monolayer culture. CLINICAL RELEVANCE: These data have implications for modeling and understanding canine cruciate ligament pathophysiology. In particular, MMP-3 could serve as a potential preventative or therapeutic target in cruciate disease.