Back to search

BIONÆR-Bionæringsprogram

HESTEFORSK Den nevro-sentrale synchondrosens anatomi og rolle i wobbler syndrom H-20-47-553

Alternative title: Anatomy of the neuro-central synchondrosis: the structure that can explain cervical vertebral myelopathy ("wobbler") in young horses

Awarded: NOK 2.5 mill.

During a project in pigs, a growth plate was discovered in the vertebrae that is well-known to human surgeons, but barely mentioned in the veterinary literature. The plate is called the neuro-central synchondrosis, and it is responsible for growth of the spinal canal through which the spinal cord runs. A narrowed spinal canal can pinch nerves in the neck and make horses unsteady on all four legs, known as wobbler syndrome. As the synchondrosis is responsible for growth of the spinal canal, if it grows poorly, it can potentially cause narrowing and wobbler syndrome. The aim of the project is therefore to describe the neuro-central synchondrosis in horses. We have been privileged to receive over three times as much material as planned. The neck of over 30 foals from approximately 9 months gestation to 1 year old has been examined using computed tomography (CT). Reading, collation and presentation of results is currently ongoing, and three tentative findings have been made: 1. There is difference in when growth closes between different plates within vertebrae. Simply put, the plates uppermost in the vertebra, towards the horse’s mane, close first. Thereafter, the middle, new growth plate; the synchondrosis, closes, and finally, the growth plates nearest the ground, in the vertebral body, close. 2. There is difference in when growth closes between the different neck vertebrae. The seven neck vertebrae are numbered from 1: nearest to the head, to 7: nearest to the tail, and when the plates are summed, they close in the following order: 7, 3, 6, 4, 5, 2, 1. 3. There is difference in whether growth is closed or not between foals, depending on age. As mentioned, there are differences between vertebrae, but generally speaking at around 8 months of age, the uppermost growth plates are closed, “scars” are still visible at the site of the midway, new growth plate; the synchondrosis, whereas the lowermost growth plates remain a little open, especially the ones nearest the tail within some of the vertebral bodies. The findings are tentative because we may still be able to add more data around the oldest ages, and because we wish to group the foals by breed as far as the material permits, to see if growth closes sooner in small ponies than in large horse breeds, or vice versa. The material also contains a large number of changes that probably represent disease, but there is already so much information to present about growth closure that disease examples will be presented in a separate, extra publication. Work is also progressing with magnetic resonance imaging (MRI) and histological validation. NMBU has acquired a strong, 3-tesla MRI-scanner that can accommodate most of the neck of small foals from the clinic, so we are looking forward to report more from these exciting techniques in future!

-

Unge hester kan utvikle cervikal vertebral stenotisk myelopati og ataksi, kjent som «wobbler syndrom» og forbundet med tap av avlsverdi, nedsatt atletisk potensial og eutanasi. Noen wobblere har osteochondrose i sine vertebrale fasettledd, men det er ikke kjent hvordan dette henger sammen forsnevringen av ryggmargskanalen i wobbler syndrom. Under forskning på gris ble det oppdaget en struktur kjent som den nevro-sentrale synchondrosen. Endene av strukturen er ansvarlige for å danne fasettleddene, og midten er ansvarlig for å danne ryggmargskanalen. Den nevro-sentrale synchondrosen er ikke beskrevet i tekstbøker for veterinæranatomi. Målet med prosjektet er derfor å lage en anatomisk beskrivelse av den nevro-sentrale synchondrosen i nakken på føll, gjennom bruk av avansert billeddiagnostikk. Beskrivelsen vil legge grunnlaget for fremtidig diagnose av sykdom i denne strukturen, med potensial til å forklare forsnevring av ryggmargskanalen og wobbler syndrom på unge hester.

Funding scheme:

BIONÆR-Bionæringsprogram