Abnormal Bone Scan Findings of the Equine Ischial Tuberosity and Third Trochanter

Abstract

Obtaining high-quality radiographs of the proximal aspect of equine limbs is difficult because of the large muscles in these regions. The use of scintigraphy may provide further information. Abnormal bone scan findings of the ischial tuberosity or the third trochanter were found in 29 adult horses with obscure hind limb lameness between 1986 and 1996 at the Large Animal Clinic of the University of Bern. Each had abnormal radiopharmaceutical uptake but not all had radiographic changes. Radiopharmaceutical uptake ratios between the ischial tuberosity and the greater trochanter were calculated. The uptake ratio in a control group of 11 clinically sound horses was lower than in 11 lame horses with subjectively enhanced radiopharmaceutical uptake.

Evaluation of the diagnostic accuracy of skeletal scintigraphy in lame and poorly performing sports horses

“…Relevance categorization was subjectively applied based upon the characteristics of increased radiopharmaceutical uptake including location, radiopharmaceutical uptake grade, whether it was diffuse, focal or linear, and between‐limb symmetry. Existing scientific knowledge on the value of increased radiopharmaceutical uptake in the diagnosis of clinically significant pathology in different anatomical regions was applied to relevance categorization …”

“…The incorporation of a skeletal scintigraphic examination alongside other imaging modalities and diagnostic procedures can provide additional clinically useful information. Its value in the diagnosis of specific lesions or injuries in combination with other imaging modalities, clinical examination, and the results of diagnostic analgesia (if performed), has been documented for several anatomic sites in horses . A relatively small number of these studies reported the sensitivity and specificity of radiopharmaceutical uptake for lesions .…”

Clinical findings associated with chronic ischial fracture in a gelding

“…Gamma scintigraphic findings in ischial fractures, in particular, are well-documented. 12,9 However, its usefulness may have been limited in this case due to the chronicity of the lesion and the considerable muscle atrophy. 13 Ultrasonography is useful in the diagnosis of ileal wing fractures but is of limited use in more caudal pelvic fractures.…”

“…7 Limited information is available on fractures of the equine ischium and they appear to be rare. 2,8,4,5,9 Ischial fractures alone have been recorded in 3/26 cases 2 , 2/19 cases 4 and 5/100 cases 5 of equine pelvic fractures. Geissbuhler and others 9 have recently described six fractures of the ischial tuberosity associated with scintigraphic abnormalities.…”

“…2,8,4,5,9 Ischial fractures alone have been recorded in 3/26 cases 2 , 2/19 cases 4 and 5/100 cases 5 of equine pelvic fractures. Geissbuhler and others 9 have recently described six fractures of the ischial tuberosity associated with scintigraphic abnormalities. The diagnosis of pelvic fracture may be confirmed by radiography under general anaesthesia 2,10 or, as in this case, in the standing animal, eliminating the necessity for general anaesthesia and hospitalisation.…”