Veterinary and Comparative Orthopaedics and Traumatology最新文献

This study integrated a locking plate system into three-dimensional (3D)-printed implants and evaluated whether directly 3D-printed locking plate holes could achieve mechanical performance comparable to their machined counterpart. In vitro mechanical tests were performed to compare a 3D-printed 3.5-mm locking plate system with a commercially available variable-angle locking system (ARIX). Locking plate specimens (n = 90) were 3D printed from Ti6Al4V in three build orientations (0, 45 and 90 degrees). A torque limit test assessed the failure points under three screw insertion torques (0.6, 1.1 and 2.0 Nm) at two angles (0 and 15 degrees). The locked screw-and-plate constructs then underwent push-out testing, with a load applied parallel to the screw axis.At 2.0 Nm, all 3D-printed specimens failed due to thread deformation, whereas the ARIX system remained intact. Specimens printed at 0-degree orientation had the highest push-out strength, comparable to ARIX plates, while those printed at 90 degrees showed significantly lower strength. A higher insertion torque (1.1 Nm) improved the push-out strength regardless of screw angulation. Low torque with angled screws led to a substantial reduction in push-out strength.The directly 3D-printed locking plate system achieved a comparable mechanical performance to machined counterparts when printed at 0-degree orientation, with appropriate torque. Optimal build orientation and careful control of insertion torque are crucial for maximizing the performance of 3D-printed locking plates.

The aim of this study was to assess fracture distribution and involvement of functional systems in cats presenting with craniomaxillofacial (CMF) trauma using computed tomography imaging. Involvement of functional systems, including the oral cavity, nasal airways and nasopharynx, orbita and eye and neurocranium, including the tympanic bulla, was assessed.The study consisted of 48 cats with complete computed tomography imaging of the skull using a '1.0-mm' slice thickness. Fractures were classified according to their anatomical location, and the involvement of functional systems was assessed.Fractures of the mandible were most common and present in 40/48 cats. Fractures of the temporomandibular joint were found in 25/48 cats. Fractures involving the maxillofacial structures were present in 36/48 cats. Fractures of the orbita, nasopharynx, zygomatic arch and neurocranium were diagnosed in 30/48, 29/48, 12/48 and 6/48 cats, respectively. Combined involvement of two or more functional systems was present in 36/48 cats. Functional system involvement of the oral cavity combined with nasal airways was found in 36/46 cats. Involvement of the nasal airways combined with the orbita and eye was found in 30/36 cats.Craniomaxillofacial trauma in cats causes multifocal, concomitant involvement of functional systems. A multimodal therapeutic approach to all potential functional deficits seems to be essential in managing craniomaxillofacial trauma in the cat.

To evaluate the feasibility and accuracy of vertebral pedicle screws in cats using a custom 3D-printed drill guide and 3D-printed vertebral columns.To simulate the surgical procedure, six vertebral columns from adult cats were 3D-printed. The columns were printed with a radiolucent material (PLA enriched with calcium carbonate-PLA+). One 3D-printed guide was created for each vertebra (from T10 to L7). Each preplanned hole was drilled and filled with a graphite cylinder for better visualization of the tunnel. All the phantoms were CT-scanned after the drilling operation. Each hole was graded using a modified classification scheme (grades 0 to 3) and compared to the planned tunnel angle. We enrolled one 5-year-old female patient with spinal trauma requiring vertebral stabilization presented at our hospital.A total of 126 holes were drilled. The overall mean screw deviation angle was 0.61 degrees (SD = 0.72). In safety evaluation, 117 (93%) screws were contained in the pedicle (grade 0), 7 screws (5.5%) were outside the pedicle by less than 0.5 mm (grade 1), and 2 (1.5%) screws were between 0.5 and 1 mm outside the pedicle. In the thoracic segment, all the holes (48/48) were classified as a grade 0, while in the lumbar segment, with a total of 78 holes drilled, there were 69 holes classified as grade 0 (88%), 7 holes classified as grade 1 (8.9%), and 2 holes classified as grade 2 (2.5%). The feline patient had suffered a T12 complete oblique vertebral body fracture. A total of six 1.7 mm screws, 20 mm long, (Fix-In, INTRAUMA) were placed: three in T12 and three in T13.Overall, there was a mean deviation of the hole angle from the planned angle of 0.61 degrees. The overall safety was 91.2% (screws graded as 0). A statistically significant association between screw grades and vertebral segment was found (p-value 0.02) as all the thoracic vertebrae are grade 0, while grade 1 and grade 2 were found only in the lumbar segment. Using pedicle screws in cats' vertebrae may reduce surgical trauma, as it requires exposure of only the most dorsal portion of the vertebral lamina, avoiding the need to expose the costal attachments. Also, placing cement dorsally is easier and can incorporate screw heads bilaterally. We effectively and safely performed the surgical procedure in one clinical case. Based on our results, the use of pedicle screws, previously applied in canine patients, could also be extended to feline patients, provided that 3D-printed guides are used to ensure accurate placement.

The purpose of this study was to compare the calculated angle of lateral opening (ALO) and open-face version obtained using an acetabular cup position assessment device (CPAD) to the known ALO and open-face version of an acetabular component. The null hypothesis was that there would be no significant differences between the ALO and open-face versions using the CPAD compared with the known values.Radiographic images simulating a sagittal plane pelvis were obtained with a BFX™ acetabular component containing a CPAD mounted on a plexiglass jig with a dual-plane inclinometer. Images were obtained at an open-face version of 0 degrees with ALO at 30, 40, 45, 50, and 60 degrees, repeated in triplicate, and were randomized. Measurements of the CPAD bars were used to calculate the open-face version, and ALO measurements were compared using a paired t-test with a p-value set at p < 0.05. Agreement was assessed with a Lin's Concordance Correlation Coefficient.The calculated ALO was not significantly different from the known ALO (p = 0.608) and showed near-perfect correlation of the ALO with a Lin's Concordance Correlation Coefficient (R _c value) of 0.994. The calculated open-face version was significantly different from the known version.The results demonstrate that the CPAD is an accurate method to determine ALO in a simulated sagittal plane pelvis radiographic view.

A hip luxation 3 years following a cementless total hip replacement was diagnosed in a 4.7-year-old neutered male Lagotto Romagnolo that presented with a non-weight-bearing left pelvic limb lameness. Orthogonal radiographs revealed a left hip luxation and an osteolytic fracture of the greater trochanter. A mass consistent with an inflammatory granuloma was identified on preoperative computed tomography scan. Surgical revision consisted of granuloma excision, replacement of the loose acetabular cup, and repair of the femoral fracture with a locking plate. Fracture biology was augmented with the use of recombinant human bone morphogenetic protein 2 (rhBMP2) impregnated collagen sponge applied around the acetabulum and femoral fracture site. Osteointegration of the prosthetics and fracture healing were documented within 3 months of revision. Long-term follow-up at 3 years postrevision showed normal limb usage and no further evidence of total hip replacement complication.

Objective:  The aim of this study was to assess the protective effect of transecting a partially ruptured cranial cruciate ligament (CCL) during tibial plateau levelling osteotomy (TPLO) surgery on postoperative patellar ligament thickness (PLT) and shortening.

Study design:  Dogs with partial CCL rupture that underwent a unilateral TPLO were included. The population was divided into two groups: remnant CCL transected (study group) and left in situ (control group). Preoperative and 6-week postoperative measurements of PLT, in three specific locations, and patellar ligament length (PLL) were collected. Risk factors for PLT and shortening were also included.

Results:  Fifty-two dogs (56 stifles) with partial CCL rupture were retrospectively included. Twenty-nine stifles (51.8%) had the remnant CCL transected (study group) and 27 stifles (48.2%) had the remnant CCL left in situ (control group). Significant differences were found on PLT measurements between pre- and 6-week post-surgery for all three ligament locations with greatest difference at the middle region. Median PLL was significantly shorter 6-week post-surgery for both groups. No significant differences in PLT nor PLL were identified between procedures where the remnant was transected or not.

Conclusion:  This study did not identify a protective effect of transecting the CCL remnant on PLT or patellar ligament shortening, contrary to other reports within the literature. Further investigation is needed in the form of prospective studies with higher number of cases to understand the clinical implications of patellar ligament thickening and shortening in dogs.

Objective:  To describe percutaneous fluoroscopy-guided placement of self-drilling, self-tapping, 3.0 mm cannulated headless compression screws (HCS) for surgical reduction of sacroiliac luxation (SIL) in cats, and to document clinical outcome.

Materials and methods:  Medical records of cats with SIL, managed by percutaneous fluoroscopy-guided placement of a 3.0 mm HCS, were reviewed. Short-term outcome was assessed by clinical examination and radiographs. Long-term outcome was assessed using an owner questionnaire.

Results:  A total of 14 cats, with 17 SIL (11 unilateral and 3 bilateral), were included. Mean postoperative sacroiliac joint reduction was 85%, median sacral purchase was 63% for unilateral and 38% for bilateral HCS, and pelvic canal diameter ratio and hemipelvic canal width ratio were satisfactory in all cases. At follow-up, all cats exhibited satisfactory clinical improvement. Radiographic assessment revealed no implant-related complications of the unilateral HCS; however, screw loosening was observed in 3/6 of bilateral HCS. Owner satisfaction was good, with 10/11 of owners being very satisfied and 1/11 being satisfied.

Clinical significance:  Percutaneous fluoroscopy-guided placement of a 3.0 mm HCS is a safe and effective method for unilateral surgical reduction of SIL in cats. Further studies are needed to establish the most appropriate procedure to treat bilateral SIL.

Objective:  Medial patellar luxation (MPL) is prevalent in small dogs; however, the causes vary, and few studies have reported tibial deformities. We aimed to conduct a detailed morphological investigation of internal tibial torsion and internal foot rotation and compare the results between MPL grades to better understand the pathogenesis of MPL.

Study design:  We performed a morphological study of the tibia and comparison with MPL grade, and established a new parameter, metatarsal orientation relative to the orientation of the tibial tuberosity, the proximal tibia metatarsal angle (PTMTA). The distal tibia metatarsal angle was also established, and tibial torsion angle (TTA), mechanical medial proximal tibial angle, medial distance of the tibial tuberosity/proximal tibial width, and crural rotation angle were compared among the grades of MPL.

Results:  The PTMTA was significantly higher in grades 3 and 4 than in the normal group. TTA, medial distance of the tibial tuberosity/proximal tibial width, and mechanical medial proximal tibial angle were significantly higher in grade 4 than in the other grades, which is consistent with previous reports. A correlation was also observed between the PTMTA and the TTA.

Conclusion:  The PTMTA functioned as a parameter that included elements of the distal tibia metatarsal angle, TTA, and medial distance of the tibial tuberosity/proximal tibial width, and is considered clinically useful because it can be visually ascertained during palpation. Our results may play a major role in surgical decision-making in the treatment of MPL.

Objectives:  To evaluate the outcome and complications in dogs with medial patellar luxation (MPL) undergoing tibial tuberosity transposition (TTT) with a locking plate and pin fixation (Plate-Pin).

Methods:  This retrospective multicenter study included 65 consecutive MPL stifle surgeries using tibial tuberosity (TT) fixation with a 5-hole locking plate and a pin. The median weight of the dogs was 6.2 kg. The grade of luxation was 2/4 in 50 stifles and 3/4 in 15 stifles. Outcomes were assessed during follow-up examinations 33 to 648 days after surgery with clinical examination and radiography. Canine Orthopedic Index questionnaires were sent to owners 6 to 39 months after surgery.

Results:  Complications were reported in 14/65 stifles, of which 8/14 were minor and 6/14 were major. After treatment of the major complications, lameness was resolved in all cases and the MPL was resolved in 64/65 stifles.

Clinical significance:  When the surgery was performed as described in this article, Plate-Pin fixation for TT during MPL surgery is a feasible technique with a lower incidence of luxation recurrence, TT avulsion, and fractures compared with recent retrospective studies with pin and tension band wire TT fixation. Further development of the locking plate TT fixation is indicated to resolve pin-related complications and to determine if fixation including a pin is necessary.