In Vitro Assessment of Compression Patterns Using Different Methods to Achieve Interfragmentary Compression during Tibial Plateau Levelling Osteotomy.

OBJECTIVES: The aim of this study was to evaluate and characterize different methods to achieve interfragmentary compression during tibial plateau levelling osteotomy (TPLO). STUDY DESIGN: TPLO was performed in 20 canine tibia models (Sawbones, Vashon, Washington, United States) using 3D-printed guides for standardization. Interfragmentary compression was assessed using pressure-sensitive films (Prescale, Fujifilm, Atherstone, United Kingdom). Seven compression methods were tested: (1) Kern bone holding forceps clamping the craniodistal aspect of the TPLO plate to the caudal aspect of the tibia (K); (2) using the distal TPLO plate dynamic compression hole (P); (3) pointed bone reduction forceps engaging the caudal aspect of the proximal bone fragment and the cranial aspect of the tibial crest (F); (4) K + P; (5) K + F; (6) F + P; and (7) K + F + P. Five measurements were obtained for each method, and each bone model was used for two measurements (single method, ± plate). The interfragmentary surface was digitalized and divided into quadrants for standardization and pixel density calculation: Q1, craniomedial; Q2, craniolateral; Q3, caudomedial; and Q4, caudolateral. One-way analysis of variance (ANOVA) and post hoc tests were used for statistical analysis. RESULTS: Mean pressures per quadrant differed significantly between methods (p < 0.001). Methods K, F, and P produced more craniomedial, craniolateral, and caudal compression, respectively. Method K resulted in loss of caudal compression (p < 0.001). Method F + P provided the most even distribution of high interfragmentary compression forces. The addition of method K to this construct (K + F + P) marginally increased cranial compression (p = 0.189 for Q1; p < 0.001 for Q2), but reduced compression caudally (p < 0.001). CONCLUSION: Method F + P provided more even interfragmentary compression. If method K were used, then combined use with method F + P would be recommended.

Subcutaneous vascular access port implantation in the axillary or femoral/external iliac vein at the time of full limb amputation in dogs.

OBJECTIVE: To report outcomes and complications after placement of a subcutaneous vascular access port (SVAP) in the jugular (jSVAP), axillary (aSVAP), and femoral or external iliac vein (fSVAP) in dogs. STUDY DESIGN: Retrospective. METHODS: Medical records from a single hospital, covering a period between September 2015 and October 2020, were reviewed to identify dogs that had an SVAP placed. Complications and outcomes for dogs who had an SVAP placed in the axillary vein, or femoral/external iliac vein during amputation for appendicular skeletal neoplasm, and in the external jugular vein were recorded and analyzed statistically. RESULTS: Subcutaneous vascular access ports were placed in the axillary vein in 13 dogs, femoral/external veins in 4 dogs, and in the jugular vein in 19 dogs. The SVAPs fulfilled their purpose throughout treatment in 12/13 aSVAP, 4/4 fSVAP, and 15/19 jSVAP. Dogs were followed for a median of 145.5 days (range 30-945 days). Minor and major complications were recorded in 1/13 and 2/13 aSVAPs, 0/4 and 0/4 fSVAPs, and 3/19 and 4/19 of jSVAPs. Two dogs with jSVAPs were euthanized due to SVAP-related complications. No difference in complication rate was detected between groups (P = .12). CONCLUSION: No difference in short-term outcome was detected between implantation sites for subcutaneous vascular access ports. CLINICAL SIGNIFICANCE: The axillary or femoral/external iliac veins offer alternative sites for placement of SVAP in dogs undergoing limb amputation.

Custom-built constrained uniaxial and rotating hinge total knee replacement in cats: Clinical application, design principles, surgical technique, and clinical outcome.

OBJECTIVE: To describe the design principles and evolution, surgical technique, and outcome for custom constrained (uniaxial and rotating hinge) total knee replacement (TKR) in cats. STUDY DESIGN: Retrospective case series. ANIMALS: Nine cats with traumatic stifle luxation (n = 8) or severe distal femoral deformity (n = 1) were considered suitable candidates. METHODS: Cats that met eligibility criteria and received a custom TKR between 2009 and 2018 by a single surgeon were included in this case series. Three generations of implant were used. Implant positioning was assessed by postoperative orthogonal radiography. Functional outcome was determined by clinical assessment, owner interview, and a feline musculoskeletal pain index questionnaire. RESULTS: Median clinical follow-up time was 12 months (range, 4-41); follow-up time was increased to 29 months (range, 22-47) when results of functional questionnaires with owner were included. Median radiographic follow-up was 12 months (range, 4-25). One cat had a catastrophic outcome. Three cats had good outcomes, and five cats had excellent outcomes. CONCLUSION: Most cats treated with custom-built TKR achieved good to excellent outcomes. CLINICAL SIGNIFICANCE: Custom TKR is a viable option for the treatment of severe pathologies of the feline stifle. Additional research is required to fully evaluate implant suitability.

Feline Distal Tibial Physeal Fracture Repair Using a Modified Cross-Pin Technique with Four Pins.

OBJECTIVE: The aim of this article was to report the surgical technique and clinical outcome of a modified cross-pin technique for the treatment of distal tibial physeal fractures in cats without postoperative external coaptation. STUDY DESIGN: This study was a retrospective clinical study. ANIMALS: A total of 9 cats were presented with fracture of the distal tibial physis. MATERIALS AND METHODS: Medical records from July 2014 to September 2018 were reviewed. In all cases, a second medial and a craniolateral Kirschner wires were added to the traditional cross-pin technique. Information reviewed included orthogonal radiographs pre- and post-surgery and at subsequent re-examinations, subjective assessment of lameness and passive range of motion, veterinary clinical assessment and completion of a functional questionnaire (feline musculoskeletal pain index) at the time of writing this report. Eight owners completed the questionnaire. The mean questionnaire follow-up time was 12.7 months. RESULTS: Uncomplicated fracture healing occurred in all patients. Two patients required implant removal due to Kirschner wire migration and protrusion through the skin at 5 and 12 months post-surgery. No other complications were noticed. Eight patients had an excellent outcome, and one patient had a good outcome. CONCLUSION: Distal tibial physeal fractures in cats can be treated successfully with the use of a modified cross-pin technique and without the use of external coaptation. Prognosis should be considered favourable for this type of fracture.