Swollen Ear Flap: Aural Haematoma, and Which Dogs Get It
A blood blister in the ear flap affected 1 in 400 UK dogs in a year. Bull Terriers and heavier, older dogs were most at risk, but not floppy-eared breeds.
Written by thecanineledger
If your dog’s ear flap suddenly swells, see your vet within a day or two. Don’t try to drain it yourself. If your dog also seems in a lot of pain, or keeps shaking or scratching the ear, call sooner.
Our note: This advice is ours. Neither source gives owner advice on timing.
An aural haematoma is a pocket of blood that builds up in the ear flap, usually on the inner side. In UK vet records from 2016, 2,249 of 905,554 dogs were diagnosed with one, about 1 in 400 (O’Neill et al., Scientific Reports 2021). The swelling can be painful, and the extra weight of the ear can distress the dog.
While floppy ears are often blamed, the study found the opposite. Breeds with long, hanging ears had lower odds than breeds with upright ears.
→ Ear Infections: Why They Keep Coming Back
1. The study
The dogs. Researchers used VetCompass, a database of anonymised UK primary-care records, covering 905,554 dogs at 887 clinics.
Funding. The Kennel Club Charitable Trust and a pet insurer funded the work. The paper states that neither, nor the Kennel Club, had any input into the study. The authors declare no competing interests.
2. Which dogs were most at risk
| Breed | Share affected in 2016 |
|---|---|
| Bull Terrier | 2.44% |
| Irish Staffordshire Bull Terrier | 1.50% |
| English Bull Terrier | 1.43% |
| Golden Retriever | 1.38% |
| Saint Bernard | 1.34% |
| Staffordshire Bull Terrier | 0.91% |
Ear shape. Breeds with folded, V-shaped ears, or semi-upright ears, had higher odds than breeds with upright ears. Breeds with long, hanging ears had lower odds. The authors write that “the results did not support this hypothesis” that hanging ears raise the risk.
Age and weight. Risk rose with age up to 8 to 12 years, then fell. Heavier dogs were more at risk, including dogs heavier than average for their breed.
Ear infections. More than half the dogs with a haematoma also had an ear infection recorded at the time.
Our note: The paper gives two figures for ear infections in these dogs, 54.6% and 54.82%.
3. Why it might happen
The authors’ theory. They propose that ears which fold in the middle are damaged by repeated folding and unfolding. Over time, the cartilage cracks, and bleeding follows.
Head shaking. Heavier dogs may also put more force on their ears when they shake their heads. Ear infections can cause head shaking and ear scratching.
Two types. The authors suggest some haematomas come from slow cartilage damage, and others follow head shaking from an ear infection. This is a theory, not a proven cause.
4. Treatment
Options. Treatment can include draining the ear, injecting a steroid into it, or surgery.
The evidence on steroids. An evidence summary of three small studies found that injecting a steroid after draining “reduced the risk of rapid recurrence”, provided drainage was frequent (Church, Veterinary Evidence 2022). However, its author rated the evidence “weak”, because of small samples and different treatment methods.
Our note: We print no drug names or doses. Ask your vet about the options.
Treat the cause. If an ear infection is present, it is likely to need treatment too.
Our note: “Treat the cause” is our inference from the link with ear infections.
→ The Itchy Dog: Allergies, Atopic Dermatitis, and What Actually Helps
5. What we could not verify
| Commonly said | What we found |
|---|---|
| “Floppy-eared dogs get ear haematomas most” | No. Breeds with hanging ears had lower odds in this study. |
| “Steroid injection stops it coming back” | Weak evidence. It reduced quick recurrence in small studies. |
| “Aural haematomas are always caused by ear infections” | Not shown. Just over half had an ear infection recorded. |
Sources
- O’Neill DG, Lee YH, Brodbelt DC, Church DB, Pegram C, Halfacree Z. Reporting the epidemiology of aural haematoma in dogs and proposing a novel aetiopathogenetic pathway. Sci Rep 2021: VetCompass study, 905,554 dogs, 2016. Funded by the Kennel Club Charitable Trust and a pet insurer
- Church R. In dogs with aural haematoma does draining and injecting corticosteroids versus drainage alone reduce the risk of recurrence? Vet Evid 2022: evidence summary of three small studies
Always confirm with your vet before acting on anything on this page.