A Retrospective Study of Postoperative Development of Implant-Induced Osteoporosis in Radial–Ulnar Fractures in Toy Breed Dogs Treated with Plate Fixation

Abstract

Objective This study aimed to evaluate implant-induced osteoporosis (IIO) development in toy breed dogs treated using internal fixation with digital radiographs as the index of pixel values. Study Design There were 226 cases (236 limbs) of toy breed dogs with radial–ulnar fractures. Pixel values were measured on radiographs immediately, 2 weeks and 1 to 12 months after surgery. The ratio of pixel values (PVR) represented the bone mineral areal density based on the humeral condyle in the same image. The dogs were grouped based on the fixation methods, age and status of destabilization. Results There was a significant decrease in the PVR at 1 to 12 months postoperatively for all cases. There were not any significant differences in PVR of antebrachial fractures between those repaired with plates using locking head screws, cortex screws or a combination of locking and cortex screws. Implant-induced osteoporosis persisted at 1 to 12 months postoperatively in dogs aged ≧6 months, while the PVR increased after 3 months in dogs aged <6 months. Based on the destabilization method, there was a significant increase in the PVR at 3 months in the plate removal group. Conclusion This study suggests that IIO occurs in small dogs treated with plates and screws. Moreover, patients aged < 6 months showed an early postoperative recovery of bone mineral areal density. Further, screw and plate removal could contribute to the recovery of bone mineral areal density.

Stress Changes in the Canine Radius after Locking Plate Fixation Using Finite Element Analysis

“…IIO occurs in small breed dogs, with decreased bone mineral density in the radius beneath the plate during the healing process of a radioulnar fracture. 4 It is biphasic, possibly due to insufficient periosteal blood supply (biological factor) at 8 to 12 weeks and reduced mechanical stress on the bone (mechanical factor) 24 to 36 weeks after implant placement. 5 In a canine radius model of IIO, the conventional plate technique resulted in higher levels of proinflammatory cytokines (tumor necrosis factor-α, interleukin-6) and bone resorption and lower bone mineral density up to 36 weeks postoperatively compared with the LP technique, suggesting A line between the center of the humeroradial joint and the center of the radiocarpal joint was defined as the functional axis of the radius.…”

Successful centralisation technique for treatment of post‐traumatic absence of the radial shaft in a dog

“…Fractures of radius/ulna are common in small breed dogs in which the most common complications are delayed union, non‐union and stress‐protection osteopenia (De Arburn Parent et al., 2017; Waters et al., 1993). The predisposition of these breeds to such fractures and related complications has been attributed to biomechanical and biological factors, such as low fracture loads of the distal aspect of the radius, lack of soft tissue coverage and poor vascularisation (De Arburn Parent et al., 2017; Muir, 1997; Muroi et al., 2021). Non‐unions can evolve into atrophic, and result in large bone defects, for the resolution of which various techniques have been described, such as the use of autologous bone graft, allograft and artificial bone materials (Massie et al., 2017; Munakata et al., 2018; Ragetly & Griffon, 2011).…”