| Ununited Anconeal Process Race Foster, DVM Marty Smith, DVM Drs. Foster & Smith, Inc. |
An ununited anconeal process (UAP) is a disorderof the elbow. It occurs when a small bony projection called the
anconeal process fails to unite and fuse with the ulna, the smaller of the bones making up the foreleg. The
anconeal process is critical for the proper formation of the elbow joint. It provides stability to the joint,
especially when the leg is extended.
Generally, the anconeal process and ulna fuse by 24 weeks of age. After this age, a lameness will develop if the
anconeal process remains separated. German Shepherds, Basset Hounds, and Saint Bernards have the highest
incidence of UAP. It is considered a genetically transmitted disorder and affected individuals should not be
bred.
What are the symptoms?
This condition can affect one or both elbows. The dog will be lame on the involved limb(s). Additionally, the
elbow may appear swollen and painful, especially when the leg is extended. Most cases are seen in young dogs
between six and twelve months of age.
What are the risks?
Quite commonly, without treatment, the joint will become severely painful and useless. The dog will walk on
three legs, or not at all if both elbows are involved. The condition worsens with age, with severe arthritic
changes occurring.
Dogs with an ununited anconeal process may have other abnormalities of the bones in the elbow joint.
Sometimes a flap or piece of cartilage may become dislodged from the bone. This is called osteochondritis
dissecans.
What is the management?
Radiographs (x-rays) are needed to confirm the diagnosis. Once confirmed, surgery is generally recommended.
Several surgical procedures can be used to either attach the anconeal process with screws, or remove it
completely. Even with surgery, the function of the elbow joint is usually compromised to some degree.
anconeal process fails to unite and fuse with the ulna, the smaller of the bones making up the foreleg. The
anconeal process is critical for the proper formation of the elbow joint. It provides stability to the joint,
especially when the leg is extended.
Generally, the anconeal process and ulna fuse by 24 weeks of age. After this age, a lameness will develop if the
anconeal process remains separated. German Shepherds, Basset Hounds, and Saint Bernards have the highest
incidence of UAP. It is considered a genetically transmitted disorder and affected individuals should not be
bred.
What are the symptoms?
This condition can affect one or both elbows. The dog will be lame on the involved limb(s). Additionally, the
elbow may appear swollen and painful, especially when the leg is extended. Most cases are seen in young dogs
between six and twelve months of age.
What are the risks?
Quite commonly, without treatment, the joint will become severely painful and useless. The dog will walk on
three legs, or not at all if both elbows are involved. The condition worsens with age, with severe arthritic
changes occurring.
Dogs with an ununited anconeal process may have other abnormalities of the bones in the elbow joint.
Sometimes a flap or piece of cartilage may become dislodged from the bone. This is called osteochondritis
dissecans.
What is the management?
Radiographs (x-rays) are needed to confirm the diagnosis. Once confirmed, surgery is generally recommended.
Several surgical procedures can be used to either attach the anconeal process with screws, or remove it
completely. Even with surgery, the function of the elbow joint is usually compromised to some degree.
| This site was created by and is maintained by Belinda Winters for BFH Bassets. If you have any questions or comments email belindawinters@bfhbassets.com |
