Specimens of ligamentum flavum, joint capsule, and dorsal lamina were collected at surgery or necropsy from 25 horses with cervical static stenosis. All horses had myelographic evidence of dorsal compression of the spinal cord caused by soft tissue and/or bone in the caudal cervical area, primarily at C6-7. Most horses also had radiographic evidence of degenerative joint disease of articular facets. Histologically 19 horses had osteosclerosis and cartilage retention in the dorsal lamina, and 24 horses had increased fibrocartilage at the ligamentum flavum attachment to dorsal lamina. The ligamentum flavum and joint capsule had fibrovascular tissue in 20 horses. Fibrocartilaginous tissue, old hemorrhage, and fat necrosis were not unusual. One horse each had a synovial cyst, eosinophilic granulomas in the joint capsule, and osteochondrosis of articular facets. These findings indicate that abnormal biomechanical forces or instability of articulations result in stretching and tearing of the ligamentum flavum and joint capsule with subsequent fibrovascular and fibrocartilaginous proliferation, osteosclerosis of the dorsal lamina, and osteophyte formation on the articular facets.
CarterDR:
Mechanical loading histories and cortical bone remodeling.
Calcif Tissue Int36:
19,
1984.
3.
ChambersJNBettsCW:
Caudal cervical spondylopathy in the dog: a review of 20 clinical cases and the literature.
J Am Anim Hosp Assoc13:
571,
1977.
4.
DeLauntaA:
In:Veterinary Neuroanatomy and Clinical Neurology,
pp. 199,
219.
WB Saunders Company,
Philadelphia,
1983.
5.
DeLauntaAHedhammerAWuFMKrookL:
Over-nutrition and skeletal disease.
Cornell Vet64(Suppl 5):58,
1974.
6.
EdwardsWCLaRoccaH:
The developmental segmental sagittal diameter of the cervical spinal canal in patients with cervical spondylosis.
Spine8:
20,
1983.
7.
EpsteinBS:
In:The Spine: A Radiological Text and Atlas,
p. 377.
Lea and Febiger,
Philadelphia,
1976.
8.
FiroozniaHBenjaminVMPintoRSGolimbuCRaficMLeitmanBSMcCauleyDI:
Calcification and ossification of posterior longitudinal ligament of spine.
NY State J Med173:
1193,
1982.
9.
FisherLFBowmanKFMacHargMA:
Spinal ataxia in a horse caused by a synovial cyst.
Vet Pathol18:
407,
1981.
10.
FraserHPalmerAC:
Equine inco-ordination and wobbler disease of young horses.
Vet Rec80:
338,
1967.
11.
FrostHM:
A chondral modeling theory.
Calcif Tissue Int28:
181,
1979.
12.
GilbertsonEMM:
Development of periarticular osteophytes in experimentally induced osteoarthritis in the dog.
Ann Rheum Dis34:
12,
1975.
13.
GrabiasS:
The treatment of spinal stenosis.
J Bone Joint Surg62A:
308,
1980.
HurovLI:
Treatment of cervical vertebral instability in the dog.
J Am Vet Med Assoc175:
278,
1979.
16.
IwasakiYAkinoMAbeHTsuruMTashiroKMiyasakaKKanadeaKIsuTItoT:
Calcification of the ligamentum flavum of the cervical spine.
J Neurosurg59:
531,
1983.
17.
KawanoNYoshidaSOhwadaTYadaKSasakiKMatsunoT:
Cervical radiculomyelopathy caused by deposition of calcium pyrophosphate dihydrate crystals in the ligamenta flava.
J Neurosurg52:
279,
1980.
18.
KubotaMBabISumidaT:
Myelopathy due to ossification of the ligamentum flavum of the cervical spine.
Spine6:
553,
1981.
19.
KubotaTSatoKKawanoHYamamotoSHiranoAHashizumeY:
Ultrastructure of early calcification in cervical ossification of the posterior longitudinal ligament.
J Neurosurg61:
131,
1984.
LanyonLE:
Functional strain as a determinant for bone remodeling.
Calcif Tissue Int36:
56,
1984.
22.
LanyonLERubinCT:
Static vs dynamic loads as an influence on bone remodeling.
J Biomechanics17:
897,
1984.
23.
MayhewIGdeLauntaAWhitlockRHKrookKRTaskerJB:
Spinal cord disease in the horse.
Cornell Vet68(Suppl 6):1,
1978.
24.
MeadeJBCowinSCKlawitterJJVan BuskirkWCSkinnerHB:
Bone remodeling due to continuously applied loads.
Calcif Tissue Int36:
25,
1984.
25.
NixonAJStashakTS:
Dorsal laminectomy in the horse. Review of the literature and description of a new procedure.
Vet Surg12:
172,
1983.
26.
NixonAJStashakTSIngramJT:
Dorsal laminectomy in the horse. Results in horses with cervical vertebral malformation.
Vet Surg12:
184,
1983.
27.
NixonAJStashakTSIngramJT:
Diagnosis of cervical vertebral malformation in the horse.
Proc 28th Am Assoc Equine Pract258:
253,
1983.
28.
OlssonSEStavenbornMHoppeF:
Dynamic compression of the cervical spinal cord.
Acta Vet Scand23:
65,
1982.
29.
PalmoskiMJBrandtKD:
Immobilization of the knee prevents osteoarthritis after anterior cruciate ligament transection.
Arthr Rheum25:
1201,
1982.
30.
ParfittAM:
The cellular basis of bone turnover and bone loss. A rebuttal of the osteocytic resorption bone flow theory.
Clin Orthop Rel Res127:
236,
1977.
31.
RamseyRH:
The anatomy of the ligamenta flava.
Clin Orthop Rel Res44:
129,
1966.
32.
ReedSMBaylyWMTraubJLGallinaAMillerLM:
Ataxia and paresis in horses. Pt. 1. Differential diagnosis.
Comp Cont Educ3:
588,
1981.
33.
SelcerRROliverJE:
Cervical spondylopathy—wobbler syndrome in dogs.
J Am Anim Hosp Assoc11:
175,
1975.
34.
StashakTS:
A surgical technique for correction of cervical vertebral stenosis in the horse.
Am Vet Med Assoc,
116th Ann Mtg,
July 1979.
35.
TrotterEJdeLahuntaAGearyJCBrasnerTH:
Caudal cervical vertebral malformation-malarticulation in Great Danes and Doberman pinschers.
J Am Vet Med Assoc168:
917,
1976.
36.
VeidlingerOFColwillJCSmythHSTurnerD:
Cervical myelopathy and its relationship to cervical stenosis.
Spine6:
564,
1984.
37.
WhitwellKE:
Causes of ataxia in horses.
In Practice2:
17,
1980.
38.
WilliamsJMBrandtRD:
Exercise increases osteophyte formation and diminishes fibrillation following chemically induced articular cartilage injury.
J Anat139:
599,
1984.
39.
WrightFRestJRPalmerAC:
Ataxia of the Great Dane caused by stenosis of the cervical vertebral canal: comparison with similar conditions in the basset hound, Doberman pinscher and the thoroughbred horse.
Vet Rec92:
1,
1973.
