Veterinary and Comparative Orthopaedics and Traumatology最新文献

Objective:  The aim of this study was to identify safe corridors for pin placement in the terminal thoracic vertebrae, lumbar vertebrae and sacrum of rabbits using computed tomography (CT) in cadaveric models.

Study design:  Computed tomographic imaging of 25 adult New Zealand white rabbit (Oryctolagus cuniculi) cadavers was evaluated. Safe insertion corridors at the cranial and caudal end cortical sections (ECS) of the vertebrae were determined using a multiplanar reconstruction software. Pins were placed to allow maximal bone purchase within the safe corridors. Post-procedure CT imaging was performed to evaluate the pin position.

Results:  The median safe corridor height in the thoracic and lumbar cranial ECS (2.54 mm; 1.39-3.97 mm) was significantly lower than that of caudal ECS (3.98 mm; 1.66-5.53 mm; p < 0.001). The mean widths of the left and right sacral safe corridors were not significantly different. Of the 99 pins placed, 70.7% of the pins were appropriately placed without vertebral canal impingement. Errors included partial canal impingement (12.1%), complete canal impingement (5.1%), inadequate bone purchase (7.1%), placement into the intervertebral disc space (1.0%) or in the incorrect ECS than intended (4.0%). The odds ratio of successful pin insertion without canal impingement was 2.77 (95% confidence interval, 1.04-7.43; p < 0.05) times higher in the caudal ECS than in the cranial ECS.

Conclusion:  The corridor identified in this study can be used as a guideline for pin placement in the thoracic and lumbar vertebrae of New Zealand white rabbits. Further biomechanical studies are required.

Objective:  The aim of this study was to use computed tomography (CT) images obtained from English springer spaniels (ESS) with different sizes of humeral intracondylar fissure (HIF) to describe the typical shape, origin and a possible propagation pattern of HIF in this breed.

Study design:  It is a retrospective analysis of 32 elbow CT from 27 ESS with incomplete HIF. Measurements included HIF articular surface length, centre of HIF at articular surface relative to the caudal edge of the supratrochlear foramen (CHIF), HIF depth and sagittal area of fissure. Measurement of isthmus area and diameter was obtained for each elbow. Humeral intracondylar fissure measurements were analysed as proportions of the isthmus. For parts of analysis, elbows were grouped by HIF area as a percentage of isthmus area (%HIF) into less than 20% (n = 10), 20 to less than 40% (n = 8), 40 to less than 60% (n = 9) and 60 to less than 90% (n = 5).

Results:  The mean isthmus diameter was 12.31 mm (range: 10.96-13.69 mm). Mean CHIF for %HIF groups less than 20%, 20 to less than 40%, 40 to less than 60% and 60 to less than 90% were 57, 74, 86 and 96 degrees, respectively. The less than 20% group was significantly lower than 20 to less than 40% group (p = 0.035) and 40 to less than 60% and 60 to less than 90% groups (p < 0.001); the 20 to less than 40% group was significantly lower than the 60 to less than 90% group (p = 0.015). Humeral intracondylar fissure articular surface length increased in a sigmoidal fashion relative to %HIF, corresponding to segmental enlargement of the fissure as %HIF increases.

Conclusion:  In ESS, HIF typically originates approximately 57 degrees caudal to the supratrochlear foramen in the sagittal plane and may propagate in a segmental fashion with lesser propagation through the proximal intracondylar region.

Objective:  To report a modified intramedullary pinning technique, and associated outcomes, for distal femoral physeal Salter-Harris type I and II fracture management in cats.

Study design:  Retrospective study including client-owned cats presented between November 2014 and February 2022 with distal femoral physeal fractures treated with an intramedullary pin and one antirotational pin inserted in the lateral femoral condyle. Collected data included signalment, fracture characteristics according to the Salter-Harris classification, surgical data (intramedullary and antirotational pin sizes), and outcome data (radiographic and functional outcomes and complications).

Results:  Thirty-one cats were included in this study. Bone healing was radiographically confirmed 6 to 8 weeks postoperatively in all cases. The majority of cats (30/31) were classified as full functional outcomes at mid-term follow-up. The overall mid-term complication rate was 3% (1/31). Implant migration was not observed and implant removal was not needed in any case.

Conclusion:  The modified intramedullary pinning technique for distal femoral Salter-Harris I and II fracture management in cats was associated with an full functional outcome.

Objective:  The aim of this study is to describe the use of String of Pearls (SOP) plates for the surgical management of feline pelvic fractures, including surgical technique, proposed indications, complications, and outcomes in a cohort of cats.

Study design:  This study is a single-center retrospective clinical case series.

Methods:  Medical records (2015-2019) of cats presenting for pelvic fractures (n = 33) were reviewed. Type of fracture, preoperative and postoperative imaging, and complications were retrospectively retrieved. Owners were contacted via questionnaire for medium- and long-term follow-up.

Results:  A total of 20 cats met the inclusion criteria. Minor intraoperative complications were encountered in three patients. One patient suffered a major intraoperative complication. Five major complications were encountered postoperatively. These included two greater trochanter osteotomy fixation implant removal and three SOP plate removal. Full function was recovered in all patients according to the owners' assessment.

Clinical significance:  The use of SOP plates in feline pelvic fractures appears to yield a consistently good outcome with a very low incidence of canal narrowing and screw loosening. SOP plates are easy to contour and to apply along the entire pelvic length.

Objective:  While it has been known for a long time that laxity in the hip joint is the primary cause of degenerative changes later on in canine hip dysplasia, limited data are available on the fundamental characteristics that define the procedure used to quantify this. The aim of this study was to evaluate the force-laxity relation to assess the repeatability of repeated cycles of stress on the hip joint and determine the force necessary tomeasure a sufficient proportion of laxity present in hip joints.

Materials and methods:  Thirty-four canine cadavers underwent a radiographic protocol including stress radiographs with increasing force using the Vezzoni modified Badertscher distension measuring device (VMBDmD). Three dogs underwent five repeat examinations. The laxity index (LI) and osteoarthritis were scored.

Results and conclusion:  The curves and the maximal LI (LI_max) were not significantly influenced by osteoarthritis, weight, gender, and side. The position of the VMBDmD influenced the curve but not the LI_max. The force-laxity curve itself and the LI_max were repeatable, which indicated that it did not cause permanent damage to the joint and also confirmed the practicability of the procedure. Ninety percent of hip joints reached sufficient laxity at a force of 95.32 N, which is realistically achievable. Further studies are necessary before extrapolating these results to patients and to further enlighten the biomechanics of stress radiographs.

Objective:  The aim of this study was to define the extent of the biceps tendon, subscapularis tendon, and cranial border of the medial glenohumeral ligament within the field of view during standard lateral shoulder arthroscopy in the dog. We also examine the effect of joint flexion on the field of view of the biceps tendon.

Study design:  This was a cadaveric study using 21 shoulders of large breed dogs. Each shoulder was explored with a 30-degree arthroscope using standard lateral ports. For each supporting structure, the margins within the arthroscopic field of view were marked with ink. In 11 shoulders, the distal margin of the biceps tendon was identified and marked first with the limb at a standing angle and then in flexion. The margins of the cranial border of the medial glenohumeral ligament were marked at the standing angle. In 10 additional shoulders, the margins of the subscapularis tendon were evaluated. Each joint was fully dissected and the portion of each stabilizing structure within the field of view was quantified.

Results:  Fifty-eight percent of the cranial border of the medial glenohumeral ligament was within the arthroscopic view. At a standing angle, 48% of the intra-articular length of the biceps tendon was within the arthroscopic view, compared to 63% with the limb flexed. Twenty percent of the subscapularis tendon was within the arthroscopic view.

Conclusion:  A significant portion of the biceps tendon and medial stabilizing structures of the canine shoulder are outside the field of view of arthroscopy through a standard lateral approach. The limitations of the arthroscopic field of view should be appreciated when evaluating the shoulder.

Objective:  The aim of this study was to determine the prevalence of contralateral cranial cruciate ligament rupture (CCLR) in dogs 8 years of age or older, weighing more than or equal to 15 kg at the time of first-side CCLR and to assess associated risks.

Study design:  It is a cross-sectional retrospective study of 831 client-owned dogs METHODS:  Medical records of dogs weighing more than or equal to 15 kgs that were more than or equal to 8 years of age at the time of first CCLR diagnosis were reviewed. Data collected included weight, sex, pre-operative tibial plateau angle, co-morbidities, time between diagnosis of first CCLR and diagnosis of contralateral CCLR. Multivariate logistic regression analysis was used to estimate odds ratio. A median follow-up period of over 112.7 months (25th/75th quartiles 75.4/157.7 months) from first CCLR diagnosis was allotted.

Results:  Eight-hundred thirty-one dogs were identified and included. About 19.1% (159/831 dogs, 95% confidence interval: 16.6-22.0%) of dogs that experience a first-side CCLR at 8 years of age or older will rupture the contralateral side, a median of 12.9 months (25th/75th quartiles 6.5/24.3 months) later. Age (p = 0.003) and breed, Golden Retrievers (p = 0.028) and Labrador Retrievers (p = 0.007), were factors significantly associated with contralateral CCLR.

Clinical relevance:  The prevalence of contralateral CCLR in medium-to-large breed dogs more than or equal to 8 years of age old is less than previously reported and the risk decreases as they age. This important information will help guide owners when deciding to pursue surgical stifle stabilization following CCLR in older dogs.

Objective:  The aim of this study was to determine the effect of plate-bone distance (PBD) and working length on 2.0-mm locking compression plate (LCP) stiffness and strain in four-point bending and torsion in a diaphyseal fracture gap model.

Study design:  A total of 54 LCP with three screws per fragment were assigned to one of nine combinations of working length (WL; short, medium, and long), and PBD (1, 1.5, and 3 mm) for a sample size of six per construct configuration. Stiffness was measured under quasistatic, nondestructive four-point compression bending and torsion. Plate surface strain was recorded using three-dimensional (3D) digital image correlation during four-point compression bending.

Results:  WL had a significant effect on overall construct stiffness in both compression bending and in torsion, with shorter WL constructs having higher stiffness (p < 0.0001). PBD had no effect on construct stiffness in compression bending; however, a significant reduction in stiffness was noted in torsion (p = 0.047) as PBD incrementally increased. WL had a significant effect on plate strain in compression bending, with shorter WL constructs having lower plate strain (p < 0.0001). PBD had no effect on plate strain in compression bending except for lower plate strain recorded in long WL constructs with 1-mm PBD, compared with 1.5- and 3-mm PBD constructs (p < 0.0001).

Conclusion:  Longer WL constructs, regardless of PBD, had lower stiffness in compression bending, while in torsion, some modulation of this effect was noted with incremental decreases in PBD. Longer WL resulted in high plate strain, regardless of PBD.