Elbow Dysplasia in Ducky

Ducky's orthopedic journey continues...

Ducky's journey with Hip Dysplasia and recovering from bilateral total hip replacements in the #hiphiphoorayforDucky series is well documented in this blog, but now its time to learn about Ducky's elbows.

At the start of every summer, we take x-rays of Ducky’s hips to evaluate the stability of both his left and right hip implants. Last summer (2023), we took x-rays of all his major joints (hips, stifles, shoulders, elbows, wrists, ankles) to establish baseline images so that we could track degenerative changes moving forward, and address them accordingly if Ducky started to show clinical signs. His hip implants are stable and the rest of his imaging came back clean, except for his left elbow. Degenerative changes were noted in his left elbow, likely secondary to elbow dysplasia. Ducky was not showing any clinical signs for pain or discomfort in that left elbow at the time, so we opted to monitor him.

Ducky's Elbow X-Rays (May 2024) - degenerative changes observed in the left elbow, right elbow healthy and normal

Elbow Dysplasia (ED) is a condition in dogs where the 3 bones that make up the elbow joint do not fit perfectly together. Over time this can cause pain, lameness (limping) and the development of osteoarthritis. The condition is similar to Hip Dysplasia, in that it is a multifactorial disease (has multiple etiologic causes). Cause considerations include congenital, hereditary, growth abnormalities, abnormal weight distribution, defects in cartilage growth, trauma to elbow joint, weight, and diet. A diagnosis of ED is made by performing elbow x-rays and examining the bony protrusions (bumps) on the ulna that are involved in the articulation (functioning) of the elbow joint.

Elbow Anatomy & the key components of Elbow Dysplasia in Dogs

• Anconeal process: a bony protrusion (bump) on the end of the ulna --> In ED, we see an ununited anconeal process (UAD), which means that this bump does not fuse to the rest of the ulna correctly during development.

• Coronoid process: two bony protrusions on the inner (medial) and outer (lateral) aspects of the ulna --> In ED, one or both of these protrusions may crack or break off from the rest of the bone, leading to pain, discomfort, and the development of osteoarthritis. The most common one to break is the medial coronoid process (FMCP).

• The third consideration in making a diagnosis for ED is evaluating for the presence of a joint incongruency or cartilage defect (osteochondrosis dissecans - OCD). It is important to not only examine this in the elbow but also in the shoulder (humerus).

Fast forward to March 2024, I noticed Ducky started to act differently. He started to slow down on walks, shift weight off his left front leg, and limp when running. We re-performed left leg x-rays in May to see if the degenerative changes progressed or if there was anything new observed. The degenerative changes in his elbow were stable and thankfully no other changes to his other bones or joints. In order to get a better understanding of his left elbow and which component of the elbow dysplasia complex was his issue, a CT scan was performed. This advanced imaging scan was the best way to determine which specific abnormality Ducky had in his elbow, and if there was something we could do from an surgical standpoint via arthroscopy. Essentially, we were looking to identify an underlying issue, like a piece of free floating bone from a fragmented coronoid process, that we could remove to reduce pain and hopefully slow down the progression of further arthritis (once arthritis is present, it cannot be reversed).

A CT scan was performed on June 5th 2024 and we indeed did find something that could be surgically removed via arthroscopy. The scan revealed a free floating bone fragment in the left elbow, measuring at ~1 cm in size (about the size of a pea). You can see the bone fragment in the left elbow in the video below at the 0:32 second mark.

CT Scan (6/2024) - the L elbow [right side of your screen] - free floating bone fragment

Once identified, we acted quickly to schedule Ducky's arthroscopy. Arthroscopy is a type of surgery that involves the use of forceps and camera to identify and remove disease through two tiny incisions. The technique is considered minimally invasive since only a few small button-sized incisions are required to use this equipment, as opposed to making an extensive/lengthy incision to visualize the entire joint with your own eyes. In arthroscopy, the camera provides the surgeon with visualization into the joint. On June 13th 2024, Ducky underwent successful arthroscopic surgery. Two free floating bone fragments were removed.

Elbow Dysplasia - Fragmented Medial Coronoid Process. Bone fragments removed during arthroscopy

So what is next for Ducky? Recovery from arthroscopic surgery involves rest and pain management. Ducky will be on a strict exercise restriction for the next 4 weeks - no running, playing, climbing stairs, or jumping. Short walks on a leash are permitted, which for Ducky's physical needs is right up his alley. After 4 weeks, we will gradually return to full activity and assess for any pain and discomfort, as there is still arthritis in that joint that may be causing him some pain as well. If that is the case, we will then put together an arthritis & pain management plan that will be best for Ducky to fit his lifestyle needs.

Ducky during recovery of L elbow arthroscopy