What causes kyphosis in dogs

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Last updated: April 4, 2026

Quick Answer: Kyphosis in dogs, often referred to as "hunchback," is primarily caused by genetic abnormalities that lead to abnormal vertebral development, resulting in an excessive outward curvature of the spine. Other contributing factors can include trauma, degenerative diseases, infections, and nutritional deficiencies, though genetic predisposition is the most common underlying cause.

Key Facts

Genetic abnormalities are the most frequent cause of kyphosis in dogs.
The condition can manifest as an excessive outward curvature of the thoracic spine.
Trauma, such as severe falls or accidents, can lead to spinal fractures and subsequent kyphosis.
Degenerative diseases affecting the spinal cord or intervertebral discs can contribute to spinal instability and curvature.
Certain nutritional deficiencies, particularly in young, growing dogs, can impact bone development and potentially lead to spinal deformities.

Overview

Kyphosis in dogs is a condition characterized by an abnormal outward curvature of the spine, often resulting in a "hunchback" appearance. While it can affect any breed, certain breeds may have a higher predisposition due to genetic factors. This condition can range in severity, from mild cosmetic concerns to significant pain and mobility issues for the affected animal.

Causes of Kyphosis in Dogs

The underlying causes of kyphosis in dogs are varied, but genetic factors are frequently implicated, particularly in congenital cases.

Genetic and Congenital Factors

Congenital kyphosis arises from developmental abnormalities that occur while the puppy is still developing in utero. These can include:

Vertebral Malformations: This is the most common genetic cause. It involves improperly formed vertebrae, such as hemivertebrae (where only half of a vertebra develops) or wedge-shaped vertebrae. These structural defects prevent the spine from developing a straight alignment, leading to abnormal curvature. Certain breeds, like the French Bulldog, Pug, and Boston Terrier, are known to have a higher incidence of hemivertebrae due to their characteristic brachycephalic (short-nosed) skull shape, which is linked to specific gene mutations affecting skeletal development.
Genetic Predisposition: While not always a single gene, a general genetic predisposition can increase a dog's susceptibility to developing spinal abnormalities that manifest as kyphosis. This can be related to complex inheritance patterns within certain bloodlines.

Acquired Causes

In addition to congenital issues, kyphosis can also develop later in a dog's life due to acquired factors:

Trauma: Severe injuries, such as falls from height, car accidents, or fights, can result in fractures or dislocations of the vertebrae. If these injuries heal improperly or lead to instability, they can cause the spine to curve abnormally, leading to kyphosis. The location and severity of the trauma will dictate the resulting spinal deformity.
Degenerative Diseases: Conditions that affect the spine and its supporting structures over time can contribute to kyphosis. These may include:
- Intervertebral Disc Disease (IVDD): While IVDD primarily causes pain and neurological deficits by affecting the discs between vertebrae, severe cases or chronic degeneration can lead to spinal instability and subsequent curvature.
- Arthritis and Spondylosis: Degenerative joint disease and bony spurs (spondylosis deformans) can stiffen the spine and, in some cases, lead to abnormal fusion or uneven growth that results in a kyphotic posture.
- Osteomyelitis: Infections of the vertebrae can cause bone destruction and instability, potentially leading to spinal deformity and kyphosis.
Tumors: Spinal tumors, whether primary or metastatic, can damage vertebral bone or surrounding tissues, leading to structural weakness and curvature.
Nutritional Deficiencies: In young, rapidly growing puppies, severe deficiencies in essential nutrients like calcium, phosphorus, or Vitamin D can impair proper bone development, potentially leading to skeletal deformities, including spinal curvature. However, this is less common in well-nourished pets today.
Inflammatory Conditions: Certain inflammatory diseases affecting the spine could, in rare instances, lead to structural changes that contribute to kyphosis.

Symptoms of Kyphosis

The signs of kyphosis can vary depending on the severity and location of the spinal curvature. Common symptoms include:

Visible hunching or arching of the back.
Reluctance to jump, run, or play.
Pain when the back is touched or manipulated.
Stiffness in the hind limbs or a "bunny hopping" gait.
Changes in posture, such as standing with an arched back.
Neurological signs, such as weakness, incoordination, or incontinence, if the spinal curvature is compressing nerves or the spinal cord.

Diagnosis and Treatment

Diagnosis typically involves a thorough physical examination, neurological assessment, and imaging studies such as X-rays (radiographs) to visualize the spine. In some cases, advanced imaging like CT scans or MRI may be necessary to fully assess the extent of vertebral malformations or associated spinal cord issues. Treatment depends on the underlying cause and severity. Mild cases may only require pain management and monitoring, while severe cases or those causing significant pain or neurological deficits may necessitate surgical intervention to correct the spinal deformity or decompress the spinal cord. Physical therapy and weight management can also play crucial roles in managing the condition and improving the dog's quality of life.