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Objective: To biomechanically evaluate an ultrahigh-molecular-weight polyethylene (UWMWPE) suture for temporary tarsocrural immobilization as a potential alternative to the existing surgical method, which uses a 4.5 AO/ASIF calcaneotibial cortical screw., Study Design: Randomized in vitro biomechanical study., Animals: Pelvic limbs (n = 20) from 10 euthanized adult dogs (average bodyweight of 29.9 kg ± 1.9 kg)., Methods: Tarsocrural joints were immobilized either with a 4.5 AO/ASIF screw or a 1 mm diameter UHMWPE suture. Limbs were loaded with 60 N, 120 N, and 180 N, each for 100 cycles. After cyclic loading, immobilizations were loaded until failure. Load at failure and mode of failure were recorded., Results: Both immobilization methods remained intact during loading with 60 N, 120 N, and 180 N. Mean and standard deviation (± SD) failure loads were higher for the cortical screw (524.9 N ± 148.7 N) than for the UHMWPE suture (387.8 N ± 105.6 N), P = .0084. The stiffness of both systems was equivalent., Conclusion: Both techniques were suitable for transarticular tarsocrural immobilization in large-breed canine cadavers. While load at failure was higher for the screw compared to the suture construct, stiffness of both methods was comparable based on the laboratory settings in this in vitro study., Clinical Significance: Based on the results of this study, both the cortical screw and the UHMWPE suture stabilized the tibiotarsal joint at clinically relevant loads. However, when exposed to high loads, the cortical screw provides increased tibiotarsal stability. Comparative data need to be collected prior to widespread use of UHMWPE sutures in clinical cases., (© 2021 American College of Veterinary Surgeons.)

Objective:  The aim of this study was to retrospectively evaluate the clinical application of the Fixin mini 1.9 to 2.5 system for the treatment of long bone fractures in cats. We proposed that the Fixin mini system would successfully stabilize long bone fractures in cats with a healing time and complication rate similar to those previously reported for feline fractures using other locking bone plate systems., Materials and Methods:  Medical records and radiographs of cats with long bone fractures stabilized with the Fixin mini 1.9 to 2.5 system were retrospectively reviewed. Signalment, body weight, bone(s) fractured, region of bone fractured, fracture classification, concurrent orthopaedic injuries, complications, time to functional union, if minimally invasive plate osteosynthesis techniques were used, plate size, number of plates, bone graft use and ancillary methods of fixation were recorded., Results:  Fifty-six fractures in 54 cats were included. Mean time to radiographic union was 8.8 weeks. Complications were recorded in 8 out of 56 fractures. Major complications occurred in 4 of 56 fractures and minor complications occurred in 4 of 56 fractures., Conclusion:  The Fixin mini 1.9 to 2.5 system had an overall complication rate and time to functional union similar to that of other implant systems used to treat feline long bone fractures and it appears suitable for repair of a wide variety of long bone fracture configurations in cats., Competing Interests: A.B.B. reports non-financial support from Intrauma S.p.A., outside the submitted work. L.A.P. reports and did workshops for Intrauma about DRD jig. All other authors report no conflict of interest., (Thieme. All rights reserved.)

Cathepsin D (Ctsd) is a ubiquitously expressed aspartic protease functioning primarily in the acidic endosomal/lysosomal cell compartment. At an age of 26 ± 1 days, mice with constitutive Ctsd deficiency (Ctsd(-/-)) die from a neurodegenerative lysosomal storage disease equivalent to the congenital neuronal ceroid lipofuscinosis (NCL) type 10 in humans. In addition to neurodegeneration, Ctsd(-/-) mice exhibit a loss of CD4(+)/CD8(+)-double-positive thymocytes and an atrophy of the intestinal mucosa. To date, it is not understood if and how these phenotypes are triggering each other. In addition, the cell type causing initiation of NCL in Ctsd(-/-) mice has not been identified yet. To investigate the tissue- and cell type-specific functions of Ctsd, we generated a novel conditional Ctsd allele by flanking the second exon with loxP sites. We compared a ubiquitous Ctsd deletion with a deletion of the protease by a Nestin-promoter controlled Cre-recombinase expression in cells of neuroectodermal origin, e.g. in neurons and astroglia, but not in microglia. First, we confirmed absence of Ctsd in the respective cell- and tissue types. The neuroectoderm specific knock-out mice survived about 5.5 days longer than the mice with ubiquitous Ctsd deletion, which was in line with the progress in brain histopathology. Atrophies of thymus and small intestine were delayed to similar extend. The conditional Ctsd knock-out mouse model established in this study not only demonstrates that this type of NCL is initiated by cells of neuroectodermal origin, but will also help to further study tissue-specific functions of Ctsd in vivo., (Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)

Objective: To report clinical experiences with the tibial plateau levelling osteotomy (TPLO) procedure in small breed dogs with cranial cruciate ligament (CCL) disease using specific, conically coupled, 1.9/2.5 mm locking plates and evaluating short-term complications and outcome., Methods: Medical records of small breed dogs (<15 kg) that underwent TPLO using 1.9/2.5 mm locking plates were reviewed retrospectively. The preoperative, postoperative and six to eight weeks postoperative tibial plateau angle (TPA) measurements were determined from the radiographic images. Lameness evaluation was assessed subjectively preoperatively and six to eight weeks postoperatively., Results: Sixty-nine small breed dogs (n = 79 stifles) were included in the study. Mean (± SD) preoperative TPA was 29.0 ± 3.4°, postoperative TPA was 5.8 ± 2.5°, and six to eight weeks postoperative TPA was 7.3 ± 4.1°. Sixteen complications occurred in 12 out of 79 TPLO procedures: three were intra-operative (intra-articular screw placement) and 13 were postoperative complications, of which nine were identified as minor complications not requiring surgical reintervention, and four as major complications requiring additional surgical intervention, including tibial tuberosity fracture (n = 1), osteomyelitis (n = 1), screw failure (n = 1), and plate breakage (n = 1). Lameness scores by clinical assessment reduced from a median value of 3/4 preoperatively to 1/4 at six to eight weeks postoperatively., Clinical Significance: 1.9/2.5 mm locking plates appear to be a valid choice of implant for the stabilization of unilateral TPLO in small breed dogs.

Objective: To compare the screw push-out strength and resistance to cantilever bending of 5 different angle-stable systems using 4 different insertion torque values to tighten locking screws., Study Design: In vitro mechanical testing of 5 screw-plate constructs., Sample Population: Screw plate constructs (n = 60) were tested; 12 of each design, 3 for each torque value., Methods: To compare push-out strength, screws were loaded in axial direction on the screw tip until loosening of the locking mechanism was recorded. For cantilever bending test, screws were loaded perpendicularly to their longitudinal axis at 2 mm of distance from the under surface of the plate. Load was applied in displacement control at 1 mm/min., Results: There was a significant difference between the 5 different angle-stable systems regarding both push-out and cantilever bending strength. There was an influence of insertion torque value on push-out strength for 2 systems and insertion torque value influenced cantilever bending behavior only in 1 locking system., Conclusions: Locking mechanisms using "thread in thread" principle provided a stronger screw push-out behavior. Screws materials and core diameter of the different screws were directly related to cantilever bending strength., (© Copyright 2013 by The American College of Veterinary Surgeons.)

Objectives: To describe fluoroscopically assisted percutaneous placement of 2.4 mm cannulated screws for fixation of artificially induced sacroiliac luxations in cats, and to evaluate the success of this technique in restoration of normal pelvic anatomy., Methods: Fluoroscopically assisted closed reduction and percutaneous fixation of sacro-iliac luxations using 2.4 mm cannulated screws was performed in cadavers of 12 cats. Pre- and postoperative radiographs and postoperative computed tomographic scans were used to evaluate screw placement, screw purchase within the sacral body, reduction of the sacroiliac joint, pelvic canal diameter ratio, and hemipelvic canal width ratio., Results: Mean total surgical time was 6 minutes and 10 seconds ± 53 seconds and mean total time of fluoroscopic screening for each procedure was 44 seconds ± 6 seconds. Mean percent of reduction was 98.33% and mean screw purchase within the sacral body was 73%. Eleven out of 12 screws were placed in a satisfactory location in the sacral body. Pelvic canal diameter ratio and hemipelvic canal width ratio indicated successful restoration of the pelvic anatomy., Clinical Significance: Our results confirm that fluoroscopically assisted percutaneous placement of 2.4 mm cannulated screws is a feasible technique for fixation of sacroiliac luxations in cats. Mechanical properties of this fixation technique need to be evaluated before the use in clinical patients.

We describe the case of a 66-year-old man with a culture-proven Legionella pneumonia after kidney transplantation. The patient developed the infection 15 days after discharge from a university hospital. Legionella pneumonia caused by Legionella pneumophila serogroup 5/10 was established by positive direct fluorescence assay, positive urinary-antigen detection and isolation of the causative agent. The infection was successfully treated by giving appropriate antibiotics, but the further course was complicated by invasive aspergillosis, cytomegalovirus pneumonia, failure of the transplanted kidney and development of septic anaemia. Four months after the diagnosis of Legionella pneumonia the patient died of multi-organ failure. The microbiological and epidemiological investigation revealed that strains from the water supply of the patient's private home were indistinguishable from the patient's isolate by amplified fragment length polymorphism analysis and sequence-based typing (SBT). Unrelated strains of serogroups 4, 5, 8 and 10 from the Dresden strain collection were of different SBT types. Thus, SBT is a very useful tool for epidemiological investigation of infections by L. pneumophila serogroups other than serogroup 1.

Objective: To evaluate the influence of a tibial plateau leveling jig on osteotomy orientation, fragment reduction, and postoperative tibial plateau angle (TPA) during tibial plateau leveling osteotomy (TPLO)., Study Design: In vitro experimental study., Animals: Large-breed canine cadavers (n=20)., Methods: TPLO was performed on 40 hindlimbs using 4 methods. Group 1: Jig; dogs in dorsal recumbency with the osteotomy parallel to the distal jig pin. Groups 2-4: No jig; dogs in lateral recumbency with the osteotomy in a vertical orientation (group 2: tibia parallel to the table top; group 3: controlled superimposition of the femoral condyles; group 4: internal rotation of the tibia). Postoperative TPA, fragment reduction, and osteotomy orientation relative to the tibial plateau were compared. Positive or negative values denoted deviation from parallel relative to the tibial plateau., Results: Postoperative TPA, fragment reduction, and proximodistal osteotomy orientation were not significantly different between groups. Craniocaudal osteotomy orientation was significantly different (P<.005) from the tibial plateau. Median deviations were -4.0 degrees (group 1), 11.8 degrees (group 2), 11.2 degrees (group 3), and 0.2 degrees (group 4). Group 1 was not significantly different from group 4., Conclusions: A jig is not essential for osteotomy orientation, tibial plateau rotation, or fragment reduction. Comparable results were achieved performing a vertical osteotomy with the tibia slightly internally rotated (10 degrees -15 degrees) and parallel to the table surface., Clinical Relevance: TPLO without use of a jig reduces surgical trauma, is less time consuming, and reduces cost.

Objective: To evaluate the effect of limb positioning and measurement technique on the magnitude of the radiographically determined tibial plateau angle (R-TPA)., Study Design: In vitro study, R-TPA was determined by 6 blinded observers and image measurement software., Animals: Five canine cadaver hind limbs., Methods: The legs were positioned on a custom-made positioning device simulating a radiographic tabletop technique in lateral recumbency. True lateral positioning was defined by superimposition of femoral and tibial condyles on the radiographic projection. Radiographs were taken while the specimens were relocated in a proximal, distal, caudal, and cranial direction with respect to the radiographic beam. For each specimen, 25 different radiographic views were obtained and 6 blinded observers determined the radiographic TPA using 2 different methods. The conventional method used precise anatomic landmarks to determine the tibial plateau. To simulate osteoarthritic changes complicating identification of these landmarks, the tangential method estimated the tibial plateau as the tangent to the central portion of the tibial plateau. After periarticular soft tissue dissection the anatomic tibial plateau angle (A-TPA) was determined. The A-TPA and the R-TPA were compared., Results: The R-TPA significantly decreased as limb position with respect to the X-ray beam changed from cranial proximal to caudal distal. The maximal mean radiographic R-TPA difference was 3.6 degrees with the first and 5.7 degrees with the second method. Regardless of the method used there was no significant difference between A-TPA and R-TPA in the true lateral position. In the peripheral positions, however, significant differences between anatomic and radiographic TPA were seen., Conclusions: Limb positioning influenced the radiographic appearance of the tibial plateau and the magnitude of the measured TPA. Cranial and proximal positioning of the limb relative to the X-ray beam leads to overestimation whereas caudal and distal positioning leads to underestimation of the TPA., Clinical Relevance: True lateral positioning of the tibia defined by superimposition of the femoral and tibial condyles should be used for accurate TPA determination before tibial plateau leveling osteotomy.

Objective: To investigate tibial plateau angles (TPA) in normal and cranial cruciate ligament (CCL) deficient stifles of Labrador retrievers., Study Design: Prospective clinical study., Animals: Eighty-one client-owned purebred Labrador retrievers., Methods: Lateral radiographs of the tibia were obtained from 2 groups of dogs. Group I (42 dogs) had CCL rupture diagnosed by arthrotomy or arthroscopy. Group II (39 dogs) had no history of orthopedic problems, no radiographic evidence of CCL rupture, and dogs were >8 years of age. The tibial axis and the tibial plateau were determined on the radiographs, and the TPA was measured using image measurement software. The TPA measurement results of groups I and II were compared., Results: Group I (CCL rupture) had a mean TPA (+/-SD) of 23.5 (+/-3.1) degrees, and group II (normal) had a mean TPA (+/-SD) of 23.6 (+/-3.5) degrees. With a P value of.97, no statistical difference was detected between the 2 groups., Conclusions: No correlation between the magnitude of TPA and CCL rupture was identified in this group of Labrador retrievers., Clinical Relevance: In Labrador retrievers, TPA should not be used as a predictor of CCL rupture., (Copyright 2003 by The American College of Veterinary Surgeons)