Objective—To obtain morphometric values for the superficial digital flexor tendon, deep digital flexor tendon, accessory ligament of the deep digital flexor muscle, and suspensory ligament in the palmar metacarpal region of Icelandic Horses.
Animals—50 nonlame Icelandic Horses in training.
Procedures—Horses included 2 stallions, 30 geldings, and 18 mares from 4 to 20 years of age with a body mass index from 149.1 to 250.11 kg/m2. Transverse ultrasonographic images were obtained with an 8- to 10-MHz linear transducer and a standoff pad. In both forelimbs, the cross-sectional area, circumference, dorsopalmar width, and lateromedial width were measured 3 times at 5 regions of interest (ROIs).
Results—The coefficient of variation for all measurements of each ROI was < 5%. Comparisons were performed among and within structures and for each variable at all ROIs. Comparisons among horses revealed homogeneity because no significant influences of age, sex, height at the withers, or body mass index were found. Additionally, a characteristic skin condition interfering with ultrasonographic examination was observed.
Conclusions and Clinical Relevance—The morphometric values of the structures examined were consistent with those reported for other breeds, although some differences were observed.
Objective—To evaluate the usefulness of multisite
quantitative ultrasonography for noninvasive assessment
of bone in horses.
Sample Population—12 healthy horses and both
forelimbs from 8 clinically normal horses.
Procedure—For in vivo measurements, various
regions of interest (ROI) were examined on the third
metacarpal bone, radius, and tibia. Precision error for
speed of sound (SOS) measurements was obtained
by measuring each ROI of 4 horses 10 times with
probe repositioning. Additionally, 3 operators measured
each aspect of the third metacarpal bone of 6
horses 5 times each. For ex vivo measurements, third
metacarpal bones were examined at 9 ROI, and SOS
measurements were performed before and after soft
tissue removal. One ROI of a single forelimb was subjected
to 96 ex vivo measurements with 3 different
Results—The lateral aspect of the third metacarpal
bone had significantly higher SOS values than the dorsal
and medial aspect of the third metacarpal bone.
No difference was obtained between SOS values of
the lateral and medial aspect of the radius. The tibia
had significantly higher SOS values than the lateral
aspect of the radius and the dorsal and medial aspect
of the third metacarpal bone. Intraoperator coefficients
of variation ranged from 0.62 to 3.15%, and
interoperator coefficients of variation ranged from
0.78 to 2.70%. Values of SOS were highest when silicone
oil was used as the contact medium.
Conclusions and Clinical Relevance—Speed of
sound measurements obtained by quantitative ultrasonography
in axial transmission mode can be used
to precisely measure superficial cortical bone properties
of third metacarpal bone, radius, and tibia in horses.
(Am J Vet Res 2002;63:1464–1469)
Objective—To evaluate a human assay for quantification
of carboxy-terminal cross-linking telopeptide of
type I collagen (CTX-I), assess the influence of age on
plasma CTX-I concentration, investigate the relationship
between plasma CTX-I and serum osteocalcin
concentrations, and determine whether concentrations
of plasma CTX-I or serum osteocalcin fluctuate
in circadian manner in horses.
Horses—75 clinically normal horses.
Procedure—Cross-reactivity between equine serum
CTX-I and CTX-I antibodies in an automated electrochemiluminescent
sandwich antibody assay (ECLIA)
was evaluated via a specificity test (ie, dilution test) and
recovery calculation. Serum osteocalcin concentration
was measured with an equine-specific osteocalcin
radioimmunoassay. To analyze diurnal variations in plasma
CTX-I and serum osteocalcin concentrations, blood
samples were obtained hourly during a 24-hour period.
Results—Results of the dilution test indicated good
correlation ( r > 0.99) between expected serum CTX-I
concentrations and measured serum CTX-I concentrations.
The calculated CTX-I recovery was 97.6% to
109.9%. Plasma CTX-I and serum osteocalcin concentrations
were correlated. Plasma CTX-I concentration
was inversely correlated with age of the horse.
No significant circadian variations in plasma CTX-I and
serum osteocalcin concentrations were detected.
Conclusions and Clinical Relevance—Results suggest
that the fully automated CTX-I ECLIA can be
used for evaluation of plasma and serum samples
from horses and may be a useful tool to monitor bone
metabolism changes. Horses in this study did not
have notable diurnal fluctuations in serum osteocalcin
and plasma CTX-I concentrations. ( Am J Vet Res 2004;65:104–109)