Dr. Greg Keller of OFA presented a seminar at the National Specialty in which he summarized the data gathered in the French Bulldog Spine Pilot Project that began about three years ago.The initial goal of this research project was to obtain radiographs of Frenchie spines in an attempt to determine how common the major types of vertebral anomalies are in French Bulldogs, the regions of the spine most often involved, and whether there is a relationship between these anomalies and clinically significant “back trouble.”
None of the dogs were reported as having had symptomatic back problems at the time that the original radiographs were submitted, either related to vertebral anomalies or to disc herniations. A follow-up questionnaire was sent out this past summer to determine whether the dogs in the database have developed symptoms attributable either to vertebral anomalies or to herniated discs since being entered in the database. Of the 106 dogs on whom follow-up responses were received, 7 were reported to have had intervertebral disc disease, and of these dogs three were reported on their initial evaluations as having identifiable calcified intervertebral discs. None of those herniated discs were anatomically related to vertebral malformations. Further follow-up questionnaires will be sent, as disc herniations generally occur at age 5 years and the average age of the dogs on whom follow up questionnaires were returned was only 42.3 months with the average age of the dogs on initial radiographic evaluation being 19.2 months. Therefore, these dogs need to be followed through the ages at which disc herniation is most likely to occur.
A total of 941 vertebral anomalies were found in those 245 Frenchies.
Of these 245 dogs, 12 (4.9%) have “normal” spines free of vertebral anomalies.
Therefore 95.1% of the Frenchies studied have spines with one or more vertebral anomalies.
There are four types of vertebral anomalies seen in Frenchies:
* Hemivertebra (wedge-shaped vertebral body)
* Butterfly vertebra (“butterfly” shaped vertebral body with central portion missing or reduced)
* Block vertebra (a pair of adjacent vertebrae fused together)
* Transitional vertebra (a vertebra showing some characteristics of two types, such as cervical plus thoracic characteristics, or thoracic and lumbar characteristics).
Of the 941 anomalies seen in this study, the frequency of each type was:
Hemivertebrae: 694 (73.8%)
Butterfly vertebrae: 170 (18.1%)
Block vertebrae 65 (6.9%)
Transitional vertebrae 12 (1.2%)
Of the 941 anomalies, the parts of the spine in which they were located are:
Cervical spine 14 anomalies (1.5%)
Thoracic spine 895 anomalies (95.1%)
Lumbar spine 32 anomalies (3.4%)
The number of anomalies per dog were:
Cervical spine:
3 dogs had 1 anomalous cervical vertebra
1 dog had 2 anomalous cervical vertebrae
1 dog had 4 anomalous cervical vertebrae
1 dog had 5 anomalous cervical vertebrae
Thoracic spine:
38 dogs had 1 anomalous thoracic vertebra
41 dogs had 2 anomalous thoracic vertebrae
35 dogs had 3 anomalous thoracic vertebrae
37 dogs had 4 anomalous thoracic vertebrae
33 dogs had 5 anomalous thoracic vertebrae
17 dogs had 6 anomalous thoracic vertebrae
11 dogs had 7 anomalous thoracic vertebrae
7 dogs had 8 anomalous thoracic vertebrae
3 dogs had 9 anomalous thoracic vertebrae
2 dogs had 10 anomalous thoracic vertebrae
1 dog had 11 anomalous thoracic vertebrae
2 dogs had 13 anomalous thoracic vertebrae
Note: from the above, note that 81% of the dogs with thoracic anomalies had five or fewer. A few dogs with extremely affected thoracic spines were noted to have compromised chest cavities, which can adversely affect the lungs and heart.
Lumbar spine:
23 dogs had 1 anomalous lumbar vertebra
3 dogs had 2 anomalous thoracic vertebrae
1 dog had 3 anomalous thoracic vertebrae
Location per dog:
Cervical spine:
C3: 1 dog had anomaly at this level.
C4: 3 dogs had anomaly at this level.
C5: 3 dogs had anomaly at this level.
C6: 2 dogs had anomaly at this level.
C7: 2 dogs had anomaly at this level.
Thoracic spine:
T1: 1 dog had anomaly at this level.
T2: 8 dogs had anomaly at this level.
T3: 25 dogs had anomaly at this level.
T4: 48 dogs had anomaly at this level.
T5: 91 dogs had anomaly at this level.
T6: 110 dogs had anomaly at this level.
T7: 105 dogs had anomaly at this level.
T8: 90 dogs had anomaly at this level.
T9: 81 dogs had anomaly at this level.
T10: 53 dogs had anomaly at this level.
T11: 36 dogs had anomaly at this level.
T12: 20 dogs had anomaly at this level.
T13: 9 dogs had anomaly at this level.
Note: 70% of the thoracic anomalies were in the region from T5 to T9
Lumbar spine:
L1: 1 dog had anomaly at this level.
L2: 3 dogs had anomaly at this level.
L3: 1 dogs had anomaly at this level.
L5: 1 dogs had anomaly at this level.
Contigous anomalies per dog:
Cervical Spine:
0 contiguous anomalies in C-spine in 3 dogs with cervical anomalies
2 contiguous anomalies in C-spine in 1 dogs with cervical anomalies
4 contiguous anomalies in C-spine in 2 dogs with cervical anomalies
Thoracic Spine:
0 contiguous anomalies in T-spine in 92 dogs with thoracic anomalies
2 contiguous anomalies in T-spine in 65 dogs with thoracic anomalies
3 contiguous anomalies in T-spine in 38 dogs with thoracic anomalies
4 contiguous anomalies in T-spine in 19 dogs with thoracic anomalies
5 contiguous anomalies in T-spine in 19 dogs with thoracic anomalies
6 contiguous anomalies in T-spine in 11 dogs with thoracic anomalies
7 contiguous anomalies in T-spine in 8 dogs with thoracic anomalies
8 contiguous anomalies in T-spine in 1 dog with thoracic anomalies
9 contiguous anomalies in T-spine in 2 dogs with thoracic anomalies
10 contiguous anomalies in T-spine in 1 dog with thoracic anomalies
13 contiguous anomalies in T-spine in 1 dogs with thoracic anomalies
Lumbar spine:
0 contiguous anomalies in L-spine in 23 dogs with lumbar anomalies
2 contiguous anomalies in L-spine in1 dog with thoracic anomalies
In sumary:
* 95.1% (233) of the 245 Frenchies studied have spines with one or more vertebral anomalies.
* Thoracic hemivertebrae were the most common anomalies.
* 81% of dogs with anomalies had 5 or fewer anomalies.
* 70% of thoracic anomalies were between T5 and T9.
* 75.6% of dogs with thoracic anomalies had 3 or fewer contiguous anomalies.
* 7 dogs have had herniated discs, none related to vertebral anomalies; further follow-up is planned as the study group of dogs ages.
