Traumatic stifle injury in 72 cats: a multicentre retrospective study.

OBJECTIVES: The aim of the study was to describe traumatic stifle injury in cats and report complications and long-term outcome. METHODS: The medical records from seven veterinary hospitals of cats treated for traumatic stifle injury were reviewed. Long-term follow-up data were collected from referring veterinarians and using the Feline Musculoskeletal Pain Index, collected from owners. RESULTS: Seventy-two cats were included in the study. The most common combination of ligament injury involved both cruciate ligaments and the lateral collateral ligament (25.4%). Medial meniscal injury was more common (66.2%) than lateral meniscal injury (59.4%). A temporary transarticular pin was used intraoperatively to aid reduction in 23/73 (31.5%) surgeries. Postoperative immobilisation was applied in 41/72 (56.9%) cats with a mean duration of 4.8 weeks. Short-term complications occurred in 40/64 (62.5%) cats. Long-term complications occurred in seven (17.5%) cats. Overall outcome was excellent in 25/61 (41%) cats, good in 13/61 (21.3%) cats, fair in 11/61 (18%) cats and poor in 12/61 (19.7%) cats. Mean length of follow-up was 29.6 months (range 0.5-204). A significantly poorer outcome was observed in cats with medial meniscal injury and those undergoing revision surgery. Use of a transarticular pin when left in situ for postoperative immobilisation was associated with a poorer outcome (P = 0.043) and a higher risk of complications (P = 0.018). Postoperative immobilisation was not related to outcome. CONCLUSIONS AND RELEVANCE: Traumatic stifle injury in cats can lead to rupture of multiple ligaments causing significant instability of the joint. Surgical treatment is associated with a high rate of short-term complications, although long-term outcome may still be good to excellent in the majority of cats (62.3%). In cats where follow-up was available, postoperative immobilisation had no positive effect on outcome and may not be required. Leaving a transarticular pin for postoperative immobilisation is not recommended as it was significantly associated with a poorer outcome and a higher complication rate.

Nanoscale Coatings for Ultralow Dose BMP-2-Driven Regeneration of Critical-Sized Bone Defects.

While new biomaterials for regenerative therapies are being reported in the literature, clinical translation is slow. Some existing regenerative approaches rely on high doses of growth factors, such as bone morphogenetic protein-2 (BMP-2) in bone regeneration, which can cause serious side effects. An ultralow-dose growth factor technology is described yielding high bioactivity based on a simple polymer, poly(ethyl acrylate) (PEA), and mechanisms to drive stem cell differentiation and bone regeneration in a critical-sized murine defect model with translation to a clinical veterinary setting are reported. This material-based technology triggers spontaneous fibronectin organization and stimulates growth factor signalling, enabling synergistic integrin and BMP-2 receptor activation in mesenchymal stem cells. To translate this technology, plasma-polymerized PEA is used on 2D and 3D substrates to enhance cell signalling in vitro, showing the complete healing of a critical-sized bone injury in mice in vivo. Efficacy is demonstrated in a Münsterländer dog with a nonhealing humerus fracture, establishing the clinical translation of advanced ultralow-dose growth factor treatment.

Repeatability of quantitative sensory testing in healthy cats in a clinical setting with comparison to cats with osteoarthritis.

Objectives The aim of this study was to evaluate the repeatability of quantitative sensory tests (QSTs) in a group of healthy untrained cats (n = 14) and to compare the results with those from cats with osteoarthritis (n = 7). Methods Peak vertical force (PVF) and vertical impulse were measured on a pressure plate system. Thermal sensitivity was assessed using a temperature-controlled plate at 7°C and 40°C. Individual paw lifts and overall duration of paw lifts were counted and measured for each limb. Paw withdrawal thresholds were measured using manual and electronic von Frey monofilaments (MVF and EVF, respectively) applied to the metacarpal or metatarsal pads. All measurements were repeated twice to assess repeatability of the tests. Results In healthy cats all tests were moderately repeatable. When compared with cats with osteoarthritis the PVF was significantly higher in healthy hindlimbs in repeat 1 but not in repeat 2. Cats with osteoarthritis of the forelimbs showed a decrease in the frequency of paw lifts on the 7°C plate compared with cats with healthy forelimbs, and the duration of paw lifts was significantly less than healthy forelimbs in the first repeat but not in the second repeat. Osteoarthritic limbs had significantly lower paw withdrawal thresholds with both MVF and EVF than healthy limbs. Conclusions and relevance QSTs are moderately repeatable in untrained cats. Kinetic gait analysis did not permit differentiation between healthy limbs and those with osteoarthritis, but thermal sensitivity testing (cold) does. Sensory threshold testing can differentiate osteoarthritic and healthy limbs, and may be useful in the diagnosis and monitoring of this condition in cats in the clinical setting.

Evaluation of osteotomy accuracy and rotational and angular alignment for cranial closing wedge ostectomy performed with and without alignment aids.

OBJECTIVE: To (1) investigate the use of K-wires as alignment aids for cranial closing wedge ostectomy (CCWO) and (2) evaluate their effect on osteotomy accuracy and angular/rotational alignment. STUDY DESIGN: Cadaveric study. ANIMALS: Cadaveric pelvic limbs (n = 20). METHODS: CCWO was performed with and without alignment aids on 20 cadaveric pelvic limbs. CT scans were performed pre- and post-operatively to evaluate tibial torsion and valgus/varus deformity. Digital photographs of the ostectomized bone wedges were used to assess divergence of the 2 osteotomies, and the area of the medial and lateral aspects measured to assess osteotomy angulation within the dorsal plane. RESULTS: Osteotomy divergence angle, the difference between the area of the medial and lateral aspects of the ostectomized wedges, and the difference between the pre- and post-operative angles of valgus/varus deformity were all significantly smaller for the alignment aid group. The difference in pre- and post-operative tibial torsion was not significantly different between groups. CONCLUSIONS: K-wires can be used successfully as alignment aids during CCWO and help to create a significantly more orthogonal osteotomy. This allows a significant reduction in the difference between the preoperative and postoperative angles of valgus or varus, which may reduce the risk of developing a clinically important iatrogenically introduced valgus/varus deformity postoperatively.

A retrospective analysis of urethral rupture in 63 cats.

The aim of this study was to investigate the short- and long-term morbidity and mortality associated with urethral rupture in cats. Medical records were reviewed from four veterinary hospitals. Diagnosis was made from retrograde urethrography or direct visualisation during surgery. Location of rupture was categorised as pre-, intra- or post-pelvic. Follow-up data were collected from referring veterinarians. Sixty-three cats were included in the study of which, males predominated (88.9%). Trauma was the most common cause (n = 35; 55.6%) with the remainder due to iatrogenic injury. Forty-eight cats (88.9%) were treated surgically and six (11.1%) managed conservatively. Significant differences between cats suffering traumatic versus iatrogenic injury included the presence of musculoskeletal injuries (P <0.001); the location of rupture (P <0.001); the degree of rupture (P <0.001); definitive management (P <0.001) and short-term complications (P = 0.026). Short-term complications were significantly associated with the following: musculoskeletal injuries (P = 0.012); uroabdomen/uroretroperitoneum (P = 0.004); azotaemia (P = 0.021); postoperative urinary diversion (P = 0.036) and >1 surgery performed (P = 0.006). Forty-seven cats (74.6%) survived to discharge. Prognostic factors associated with survival to discharge included the presence of musculoskeletal injuries (P = 0.017); cause of rupture (P = 0.017); location of rupture (P = 0.039) and definitive management (P = 0.020). Twenty-four cats (57.1%) suffered short-term complications and 10 (27.0%) suffered long-term complications. Of those cats surviving to discharge 30 (71.4%) had a good outcome. Median follow-up was 16 months. Outcome was significantly associated with cause of rupture (P = 0.04); short-term complications (P = 0.03) and long-term complications (P <0.001). In conclusion, a significantly greater proportion of cats with iatrogenic injuries survived to discharge and had a good outcome compared with those that suffered trauma.