RREH Surgery Weeks 7 and 8

Weeks 7 and 8 went by more quickly than I expected. Having the routine of teching surgeries down helps make the day go by faster and with less stress. At this point in my fellowship my focus is on improving one thing per surgery in order to make slow but steady progress. Some of the interesting surgeries I was involved in include a condylar fracture repair, a bilateral lateral digital extensor tenectomy on a horse with stringhalt in the hind legs, and a bilateral mastectomy. Condylar fracture repairs are for the treatment of a fracture of the distal portion of the third metacarpal bone (MCIII) in the horse. These fractures tend to occur distally on the limb (the portion of MCIII closer to the hoof) and are often nondisplaced (a crack in the bone that hasn’t changed the position of the bone). Simpler forms of these fractures (as in the surgery I was in on) are repaired with a pair of screws (depending on the length of the fracture) that act to pull the bone tighter over the cracked area to allow it to heal with support. Because these fractures are not uncommon in the horse racing industry, the surgeons at RREH are experienced with their repair and can make the process look quick and easy. The surgeon first references radiographs of the horse’s fracture and uses their knowledge of the anatomy of the horse to find the site to drill. Once the drill bit is driven into place, radiographs are taken by technicians with the guidance of the surgeon in order to assess the eventual placement of the screw over the fracture. Rarely is an adjustment needed after the first set of radiographs. A second set of radiographs is taken after the screw(s) are placed in order to assess the repair. The surgery is then complete and the horse is taken to the fracture recovery stall to recover.

Placing a screw in the condylar fracture. The surgical assistant (intern) is using a bulb syringe to douse the screw in antibiotics as it is placed in the limb-this is part of the effort to prevent infection of the surgical site.

Stringhalt is a condition in which a horse’s hind limbs flex in a more intense manner when it picks its foot up to take a step. Imagining a horse lifting its hind foot quickly all the way up to its belly unintentionally is a good way to picture this condition. While this motion is not believed to hurt the horse, it can affect the performance of the horse and hinder its ability to do its assigned job. The patient we saw had stringhalt in both hindlimbs, and it was pronounced enough that the owners elected surgical treatment. The surgical treatment for stringhalt is to perform a tenectomy (transection and removal of a portion) of the lateral digital extensor tendon. This is what was performed on our patient. The surgeon first makes an incision over the lateral digital extensor tendon at the site where they wish to transect it. The tendon is then dissected out from its surrounding tissue and cut to act as a sort of tension release for the limb. The incision is then closed, bandaged and the patient will hopefully see improvement in his condition over the next few weeks.

 Dissecting out the tendon of the lateral digital extensor before cutting it. The legs are suspended on a hoist in order to keep them straight, stable and at relatively eye level for the surgeon.

Mastectomies are rarely performed on horses so it was a privilege to get to see one performed. Our mastectomy patient had firm masses in and surrounding her udder, and it was decided that the best treatment was removal of the mammary tissue. A mastectomy is prepped similar to a stallion castration in regards to the relative region of the surgical site and the solution used to prepare the site. The surgery itself is ultimately a dissection of the mammary tissue and the masses surrounding it. The surgeon is careful to leave enough skin with their incision so that they can close the site when the tissue removal is complete (it leaves quite a large hole!). A sample and a culture of the removed tissue was collected for analysis to help determine the prognosis of the patient. 

Beginning the dissection.

About halfway through dissection.

The removed mammary tissue and surrounding masses.

Placement of the first suture (you can see how big the hole is from the removed tissue).

Making progress on closure. The white gauze being placed temporarily into the surgical site is infused with antibiotics as a measure against infection.

Almost finished! The gauze is tied end to end and is left sticking out as you can see in this image so that it may be removed without reopening the sutures.