The patient is positioned in lateral recumbency with the fractured limb uppermost and the fracture approached as has been described. Once exposed, the fracture is reduced using pointed reduction forceps. The limb is extended and caudal and distal traction is applied to the pointed reduction forceps to bring the fracture into reduction.
Usually an 8-12 hole narrow plate is appropriate. LCP, LC-DCP or DCP have all been used successfully in this location. A soft aluminum template of appropriate length is contoured for application over the proximal olecranon extending distally onto the ulna. The fracture may need to be held in reduction by an assistant holding the reduction forceps while contouring the template.
The plate is bent to match the previously contoured aluminum template.
After inserting a cortex screw into the proximal aspect of the olecranon through the plate, the fracture is usually anatomically reduced and compressed using the dynamic compression attribute of the plate or, if a wide gap exists, with an Articulated Tension Device (ATD) as shown here.
Once the fracture is reduced and the plate applied to each side of the fracture an intraoperative radiograph should be taken to confirm reduction and plate position. In addition, radiographs taken at this time allow the surgeon to assess and, if needed, modify the preoperative plan.
Placement of the remainig screws
The remaining screws are inserted, with the cortex screws being placed prior to insertion of any locking head screws. The proximal screws should gain purchase in the dense cortical bone of the cranial metaphysis of the olecranon. Take care that the screws adjacent to the trochlear notch do not penetrate into the joint.
1-2 locking head screws are usually placed adjacent to the fracture in each fracture fragment and one at or near the ends of the plate.
Whenever possible, one interfragmentary screw should be placed to prevent that only the plate crosses the fracture line. By placing such a screw rotational stability is increased because the entire area between the plate and the screw crossing the fracture line is solidly fixed. The screw can be inserted in lag fashion or as plate screw.
In horses over a year of age the screws distal to the articular surface of the radius can engage the caudal cortex of the radius if deemed necessary. If these screws engage the radius in individuals less than 7 months of age this may lead to incongruity of the elbow joint.
Antibiotic impregnated polymethylmethacrylate beads are placed along the plate prior to surgical wound closure. The wounds are closed routinely and are covered and protected with a bandage until the skin staples or sutures are removed. Some surgeons prefer to use suction drains, but the author does not routinely use them.
5. Overview of rehabilitation
The stent bandage is removed after 72 hours post operatively. Postoperative treatment depends on the age of the horse. Foals are kept in stall rest for a minimum of 60 days, adult horses for approximately 90 days. The first half of the period hand-grazing only is advised, followed hand-walking exercises in the second half of the period. Follow up radiographs are taken at 60 resp. 90 days. If healing appears to be progressing without complications the horse is gradually transitioned to free paddock exercise.
The implants are left in place unless complications appear. More information about plate removal can be found here.
Plate removal after the ulna fracture has healed is strongly discouraged because of potential re-fracture of the ulna during recovery along empty screw holes. Therefore, whenever possible plate removal is performed in the sedated, standing horse. For more information please see additional material "Implant removal and complications".
Occasionally specific situations (explicit wish of the owner, etc.) may lead to implant removal and rarely selected screws have to be removed but the plate is left in place.
The only real indication of implant removal is chronic, non-resolving infection.
Chronic infection is usually diagnosed because intermittent lameness and subsequent opening of a fistulous tract at the surgical wound draining purulent material. Through cleaning of the fistulous tract and repeated flushing with physiologic saline and mild antiseptica the tract eventually clears up and the skin closes. As soon as the tract opens lameness disappears. With time, however, another pocket containing purulent material accumulates at the same spot associated with increasing lameness and the whole cycle repeats itself.