Biomechanical evaluation of four surgical techniques for ventral stabilization of the atlantoaxial joint in dogs

ABSTRACT Purpose: This study compared, through biomechanical evaluation under ventral flexion load, four surgical techniques for ventral stabilization of the atlantoaxial joint in dogs. Methods: In total, 28 identical atlantoaxial joint models were created by digital printing from computed tomography images of a dog, and the specimens were divided into four groups of seven. In each group, a different technique for ventral stabilization of the atlantoaxial joint was performed: transarticular lag screws, polyaxial screws, multiple screws and bone cement (polymethylmethacrylate-PMMA), and atlantoaxial plate. After the stabilization technique, biomechanical evaluation was performed under ventral flexion load, both with a predefined constant load and with a gradually increasing load until stabilization failure. Results: All specimens, regardless of stabilization technique, were able to support the predefined load without failing. However, the PMMA method provided significant more rigidity (p ≤ 0.05) and also best resisted the gradual increase in load, supporting a significantly higher maximum force (p ≤ 0.05). There was no statistical difference in flexural strength between the transarticular lag screws and plate groups. The polyaxial screws method was significantly less resistant to loading (p ≤ 0.05) than the other groups. Conclusions: The PMMA technique had biomechanical advantages in ventral atlantoaxial stabilization over the other evaluated methods.

Comparative evaluation of three laparoscopic cholecystectomy techniques in rabbit's model

Purpose: The aim of this randomized study was to compare the complications and perioperative outcome of three different techniques of laparoscopic cholecystectomy (LC). Changes in the liver function test after LC techniques were investigated. Also, we compared the degree of postoperative adhesions and histopathological changes of the liver bed. Methods: Thirty rabbits were divided into three groups: group A) Fundus-first technique by Hook dissecting instrument and Roeder Slipknot applied for cystic duct (CD) ligation; group B) conventional technique by Maryland dissecting forceps and electrothermal bipolar vessel sealing (EBVS) for CD seal; group C) conventional technique by EBVS for gallbladder (GB) dissection and CD seal. Results: Group A presented a longer GB dissection time than groups B and C. GB perforation and bleeding from tissues adjacent to GB were similar among tested groups. Gamma-glutamyl transferase and alkaline phosphatase levels increased (p ≤ 0.05) on day 3 postoperatively in group A. By the 15th postoperative day, the enzymes returned to the preoperative values. Transient elevation of hepatic transaminases occurred after LC in all groups. Group A had a higher adherence score than groups B and C and was associated with the least predictable technique. Conclusions: LC can be performed using different techniques, although the use of EBVS is highly recommended.

Prospective clinical assessment of tibial tuberosity advancement for the treatment of cranial cruciate ligament rupture in dogs

Abstract Purpose: To evaluate clinically dogs that underwent tibial tuberosity advancement (TTA) six months previously. Methods: Dogs of various breeds, gender, weight, and age that had CCL rupture and underwent TTA for treatment were included in this study. Parapatellar arthrotomy was performed in all patients to assess the joint for a ruptured ligament and meniscal injury before the TTA. The appropriate cage for the TTA was chosen with planning surgery. The surgical procedure was performed according to the literature, using a modified Maquet technique. Six months after surgery, lameness during walking; muscular atrophy; crepitation, cranial drawer and tibial compression tests and quality of life based on owner's evaluation were assessed. Results: Postoperative complications were observed in only one knee (4.76%), with a surgical site seroma. The mean lameness score at walking was 0.29 (± 0.64). The mean score regarding muscular atrophy was 0.95 (± 1.56). The mean score of the cranial drawer test, in a range from 0 to 5, was 1.52 (± 1.54). The owners rated the dog's quality of life as excellent in 44%, good in 30%, and moderate in 17%. Conclusion: This clinical study supports the affirmation that patients who undergo TTA for treatment of CCL rupture have an acceptable response.