Traumatic radius and ulna (antebrachial) fractures are common in dogs and cats and often require surgical treatment for optimal outcome (Figure 14.1). The current standard‐of‐care techniques involve open reduction of the fracture and placement of either a bone plate (applied on the cranial or medial radial surfaces) or closed reduction with an external skeletal fixator (ESF) [1–3]. The choice of implants is dictated by patient size, fracture configuration, and surgeon preference. In particular, locking plates have recently become an attractive alternative to conventional plating for the treatment of radius and ulna fractures. In this chapter, we will review specificities of locking plate application for traumatic antebrachial fractures, including the types of approaches and fracture reduction techniques that can be used with this type of implant.

Conventional osteosynthesis (CO) of radius fractures has been associated with fair to good clinical outcomes with reported healing times of 54–90 days. Unfortunately, complication rates of up to 48%, including delayed healing, infection, pin track drainage (when using ESF) and implant failure, have been reported (Figure 14.2) [4–9]. Furthermore, 25% of these complications are severe and include catastrophic failure of the repair and nonunions. These shortcomings likely result from a combination of factors, including poor fracture biology and inappropriate mechanical environment. As a result, longer healing times may be expected, and, accordingly, relatively strong bone plates are often used in an attempt to prevent implant fatigue failure before bone union occurs [8, 10, 11]. This strategy, however, may result in significant osteopenia of the bone underneath the plate and increases the risk of secondary fracture. This risk is further potentiated with the use of open approaches that disrupt fracture biology, and during which relatively short plates are typically used, creating stress concentration at the proximal aspect of the plate.

Direct surgical approach of the fracture during CO has a negative impact on periosteal vascularization, and the use of conventional bone plates may further deplete the viability of the periosteum [12, 13]. The importance of periosteal vascularization during bone healing is critical in all breeds, but may be more so in small and toy breeds due to the paucity of endosteal and medullary supply [14]. It has been reported that in dogs less than 6 kg, internal fixation or external coaptation are associated with complication rates ranging from 54% to 83% [15, 16]. In these cases, the use of locking implants could prove advantageous, as they significantly reduce damage to the periosteum, while providing mechanical advantages compared to standard plates. The preservation of periosteal blood supply should favor early formation of a callus and expedite healing of the fracture while limiting osteonecrosis under the bone plate. Faster bone healing may, in turn, allow for the safe use of relatively smaller implants, as the required implant fatigue life is decreased. While studies are lacking to support these hypotheses, it is our belief that locking implants have the potential to mitigate complications associated with internal fixation of radius fractures in all patients, and particularly in toy‐breed dogs. The use of these implants in combination with adherence to biological osteosynthesis principles will likely offset some of the complications seen in CO of antebrachial fractures.