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Ununited Anconeal Process
Ununited anconeal process has been reported in numerous large and giant breeds of dog, as well as some chnodrodystrophoid breeds such as Basset Hounds. The most commonly affected breed is the German Shepherd.
The joint affecting the humorous-ulnar area (elbow-illustration normal elbow) joint is formed by the articulation of the humorous and the ulna. It is responsible for stabilizing the joint and restricting extension of the elbow. The anconeal process fits into the hole of the humorous when the elbow is extended.
In certain breeds the anconeal process which is part of the ulna does not fuse. If not fused by 20 wk. of age this bone will stay ununited.(illustration ununited anconeal process)
Due to the non-union degenerative joint disease develops as a result of instability in the joint.
Clinical Signs:
Age of onset of clinical signs ranges from 4-8 months, although signs may appear in animals as young as two months and as old as five years.
Males are more commonly affected than females.
May affect both fore limbs and levels of pain and lameness may vary.
Pain is elicited on manipulation of the elbow, particularly extension.
Restricted range of movement in the elbow joint.
Swelling of the elbow
Diagnosis:
Radiographs of the elbow show evidence of the disease. Arthritis may or may not be present.
Treatment:
Options include conservative or surgical management .Young dogs may be best managed with surgery. See Tylenol
Surgical options include
-Removal of the anconeal process.
-Screwing the bones together
-Removing part of the ulna or a combination of the screwing and removal of bone.
Techniques that preserve the anconeal process may give better long-term success than removal of the process.
Nutraceuticals are also warranted i.e. glucosamines, MSM, and omega fatty acids.
Prevention:
This is very likely a genetic dysfunction. Therefore, affected animals should not be used for breeding or the parents of the affected animal.