RESUMEN
The utilization of antibiotic-loaded cement spacer in the induced membrane development has been a debate topic in human medicine. To the best of the author's knowledge, these combinations have not yet been evaluated in birds. Therefore, this study assessed induced membrane formation using radiography and histology, in a segmental defect of a chicken radius, with or without the addition of cefazolin. Thirty 18-month-old healthy chickens were divided into two equal groups: G1-bone defect filled with bone cement; G2-bone defect filled with cefazolin powder-loaded bone cement. Radiographic examinations of the left forearm were taken immediately after surgery and at 7, 15, and 21 postoperative days. For the collection of the induced membranes, five chickens in each group were euthanized at 7, 15, and 21 days after surgery. Radiographically, the bone cement was identified as a radiopaque structure occupying the bone defect in both groups. Mild new bone formation in at least one of the fractured extremities of the bone defect was seen only 21 days after surgery in most chickens. Histologically, there was no difference in the mean thickness of the induced membrane between groups at all time points. Multifocal multinucleated cells differed between groups at 7 (G1 > G2) and 21 (G2 > G1) days after surgery. Mononuclear inflammatory infiltrate differed between groups only on day 21 (G1 > G2). Fibrous tissue proliferation did not differ between groups at all evaluation times. Blood vessel density differed only at 21 days postoperatively (G2 < G1). Multifocal areas of cartilage differed between groups at all time points (G1 > G2). In conclusion, cefazolin mixed with bone cement did not affect thickness of the induced membrane, but did result in a negative effect on some histological aspects, such as fewer vessels, less multifocal areas of cartilage, and persistence of inflammation.
RESUMEN
This study aimed to evaluate reticulated hyaluronic acid alone or associated with ozone gas in the treatment of osteoarthritis due to hip dysplasia in dogs. Fourteen client-owned dogs were randomly assigned into two groups: Group 1-single intra-articular injection of hyaluronic acid; Group 2-single intra-articular infiltration injection of hyaluronic acid associated with ozone gas. Each hip joint received an average of 0.75 mL of reticulated hyaluronic acid ultrasound-guided. Ozone gas at a dose of 45 µg/mL was incorporated into hyaluronic acid by insufflation. Dogs were evaluated for body condition scoring, orthopedic examination and radiographic scores of the hip joints, goniometric measurements of the hip joints, visual gait score, and kinetic analysis. The evaluations were conducted immediately before treatments (M0), and at days 30 (M1), 60 (M2), and 90 (M3) after treatments. There were no significant differences in body mass and body condition scoring (5-point scale) in each group in all evaluation moments. The scores of orthopedic examination of the hip joints showed statistical differences in each group between moments (M0 > M3), but differences were not observed between groups. No statistical differences were found for radiographic scores in each group between moments, but differences were observed between groups immediately prior to treatments (G1 > G2) and 90 (G1 > G2) after treatments. Goniometric measurements of hip flexion and extension showed no significant differences in each group between moments or between groups. No statistical differences between groups were found concerning the lameness score. There were significant differences for lameness score among moments in Group 1, being M0 > M2 and M0 > M3, and Group 2 in which M0 > M1, M0 > M2, and M0 > M3. The mean percentage of change of PVF and VI between M3 and M0 in Group 1 was almost null and in Group 2 was positive, being 31.1 ± 29.4 and 10.6 ± 25.4, respectively. In conclusion, the intra-articular viscosupplementation alone or associated with ozone gas allowed improvement of lameness scores and orthopedic examination score. In Group 2 the association of ozone gas had better results on kinetic analysis.