Nuclear scintigraphic assessment of the thoracolumbar synovial intervertebral articulations.
BACKGROUND
The results of nuclear scintigraphic examination of the thoracolumbar synovial intervertebral articulations (facet joints) have to date been poorly documented.


OBJECTIVE
To establish an objective scintigraphic grading system for the facet joints; to investigate the relationship between the presence or absence of clinical signs of back pain and increased radiopharmaceutical uptake (IRU); and to compare the results of scintigraphy and radiography.


METHODS
Nuclear scintigraphic images of the 13th thoracic (T13) to first lumbar (L1) vertebrae were graded subjectively (visual assessment of the image) and objectively (using region of interest analysis) from 31 clinically normal horses in full work (Group N) and 65 horses with clinical evidence of thoracolumbar region pain and osteoarthritis of > or = 1 facet joint (Group B). Sensitivity and specificity of IRU for detection of back pain and radiographic abnormalities were assessed. A Spearman correlation was performed to test for an association between the grade of IRU and the classification of radiographic abnormality.


RESULTS
The objective scintigraphic grades were matched by 96.7% of subjective grades. IRU was seen more commonly in Group B (61.5%) than in Group N (25.8%), and moderate or intense IRU was only seen in Group B. The strongest association between radiographic abnormalities and scintigraphy was seen in horses with intense IRU.


CONCLUSIONS
Moderate or intense IRU in a facet joint is more likely to be seen in horses with back pain than in clinically normal horses.


CONCLUSIONS
Nuclear scintigraphy is a potentially useful tool in the evaluation of a horse with thoracolumbar region pain.
Centre for Equine Studies, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, UK.
A
A
Gillen
S
S
Dyson
R
R
Murray
D000818:Animals; D006734:Horse Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000473:pathology; D006736:Horses; D007592:Joint Diseases / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D011859:Radiography; D011877:Radionuclide Imaging / Q000662:veterinary*; D012680:Sensitivity and Specificity; D013122:Spinal Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000662:veterinary*; D013583:Synovial Membrane / Q000000981:diagnostic imaging* / Q000473:pathology; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*