Objective—To determine outcome of percutaneous ultrasound-guided desmoplasty with simultaneous fasciotomy for proximal suspensory desmitis (ie, desmitis of the origin of the suspensory ligament) in horses that have not responded to stall rest.
Design—Retrospective case series.
Procedures—Medical records of horses with proximal suspensory desmitis treated by means of desmoplasty with fasciotomy were reviewed. Follow-up information was obtained through telephone conversations with owners and trainers of the horses or by examination of horses at the hospital.
Results—23 of the 27 (85%) horses, including 3 of 4 horses with forelimb lesions and 20 of 23 horses with hind limb lesions, were able to return to full work after surgery and rehabilitation. All horses had ultrasonographic evidence of healing of suspensory ligament lesions.
Conclusions and Clinical Relevance—Results suggest that desmoplasty with fasciotomy is a viable treatment option in horses with proximal suspensory desmitis that have not responded to stall rest.
Objective—To determine clinical, scintigraphic, radiographic,
and arthroscopic findings and results of treatment
in horses with lameness attributable to subtle
osteochondral lesions of the shoulder joint.
Procedure—Medical records were reviewed, and
results of physical examination, scintigraphy, radiography,
arthroscopy, and treatment were recorded.
Results—Severity of lameness ranged from grade 1
to 4. Response to shoulder flexion or extension was
variable. Twelve horses had a narrow upright foot.
Intra-articular anesthesia of the shoulder joint localized
the cause of the lameness to the shoulder joint in 9 of
10 horses. Scintigraphic abnormalities were detected
in 4 of 6 horses. Radiographic lesions were subtle and
included glenoid sclerosis, focal glenoid lysis, small
glenoid cysts, and alterations in the humeral head contour.
Arthroscopic evaluation confirmed clefts in the
glenoid cartilage, glenoid cysts, a humeral head cyst,
fibrillation of the humeral head cartilage, cartilage fragmentation,
or a nondisplaced fracture of the humeral
head. After treatment, 12 horses returned to their previous
level of performance, 1 was sound for light riding,
1 remained lame, and 1 was euthanatized
because of chronic lameness.
Conclusion and Clinical Relevance—Results suggest
that a combination of physical examination,
scintigraphy, and radiography is necessary to diagnose
subtle osteochondral lesions of the shoulder
joint in horses. Arthroscopy can be used to confirm
the diagnosis and treat cartilage and subchondral
bone lesions. Young and middle-aged horses with
subtle osteochondral lesions of the shoulder joints
have a good prognosis for return to performance following
arthroscopic treatment. (J Am Vet Med Assoc
Objective—To determine whether intraluminal distention
and subsequent decompression of the equine
jejunum affects intestinal blood flow, hemodynamics,
and microvascular permeability.
Animals—5 healthy adult horses.
Procedure—Horses were anesthestized and underwent
exploratory laparotomy. Two jejunal segments
were identified as sham-operated or instrumented
segments. After baseline values were obtained, intraluminal
distention was created in the experimental
segment to induce an intraluminal pressure of 18 cm
H2O. After 120 minutes of distention, the intestine
was decompressed for 120 minutes. Mesenteric
blood flow, oxygen delivery, oxygen consumption,
microvascular permeability, wet weight-to-dry weight
ratio, neutrophil infiltration, and vascular resistance
were determined and comparisons made among control,
sham-operated, and experimental segments.
Results—Mean jejunal blood flow was 21.4 ml/min
per kg. There was a significant decrease in mesenteric
blood flow to the distended intestine (13.4
ml/min per kg). Blood flow increased significantly during
the decompression period (340% of baseline
blood flow). Intraluminal distention and subsequent
decompression resulted in a significant increase in
microvascular permeability, as determined by the
osmotic reflection coefficient. Oxygen delivery and
oxygen content decreased significantly during the distention
period and increased during decompression.
Morphologic evaluation revealed a significant
increase in edema and neutrophil infiltration after distention
and decompression, compared with results
for the sham-operated or control segments.
Conclusions and Clinical Relevance—Intraluminal
distention and decompression of the equine jejunum
results in low-flow ischemia and edema, which may
contribute to adhesions and ileus in the postoperative
period after surgery for obstructions of the small
intestines. (Am J Vet Res 2001;62:225–236)
Objective—To identify factors associated with outcome (ie, survival and return to function) following treatment of horses with septic tenosynovitis.
Design—Retrospective case series.
Animals—51 horses with septic tenosynovitis.
Procedures—Information was obtained from medical records and through follow-up conversations with owners. Factors analyzed for an association with outcome included affected limb, etiology, duration of clinical signs prior to examination, presence of complications, primary treatment, secondary treatments, number of surgical procedures, and hospitalization time.
Results—Concurrent complications were identified in 41 (80%) horses. The primary treatment consisted of through-and-through lavage in 26 (51%) horses, tenoscopy in 20 (39%), and tenosynoviotomy combined with lavage in 5 (10%). Forty (78%) horses were discharged, and 37 (73%) survived at least 1 year after surgery; 21 of the 37 (57%) returned to their previous or a higher level of performance. Percentages of horses that survived 1 year after discharge and percentages that returned to their intended use did not vary significantly among treatments. Horses with tendon rupture or sepsis of an adjacent joint were significantly less likely to survive. Horses with tendon injury or pannus were significantly less likely to return to their intended use.
Conclusions and Clinical Relevance—Results suggested that various factors were associated with outcome in horses with septic tenosynovitis. However, surgical technique was not found to be associated with survival rate or rate of return to intended use.
Objective—To determine clinical and ultrasonographic
abnormalities in horses with primary desmitis of
the palmar or plantar annular ligament (PAL) and the
response to treatment.
Procedure—Data collected from medical records
included signalment, horse use, affected limb, severity
and duration of lameness, results of diagnostic
tests performed, ultrasonographic findings, treatment,
Results—All horses had a prominent swelling in the
region of the affected PAL, and signs of pain were evident
during palpation of the swelling. In all horses,
the affected PAL was thicker than normal as determined
ultrasonographically. Twenty horses had hypoechoic
regions in the PAL. Four horses, including 1
horse with 3 affected limbs, were treated by means
of PAL desmoplasty, 9 were treated by means of PAL
desmotomy, and 12 were treated with rest. Follow-up
information was available for 21 horses. All 4 horses
that underwent PAL desmoplasty, 4 of 7 horses that
underwent PAL desmotomy, and 7 of 10 horses treated
with rest alone became sound.
Conclusions and Clinical Relevance—Results suggest
that primary desmitis of the PAL may be a cause
of lameness in horses. Although significant differences
in outcome between horses treated with rest
alone versus PAL desmoplasty versus PAL desmotomy
were not identified, because it is less invasive,
PAL desmoplasty should be considered for treatment
of horses with PAL desmitis that do not respond to
conservative treatment and do not have any evidence
of constriction of the digital flexor tendons. (J Am Vet
Med Assoc 2005;226:83–86)
Objective—To assess changes in systemic hydration,
concentrations of plasma electrolytes, hydration and
physical properties of colonic contents and feces, and
gastrointestinal transit in horses with access to large
amounts of grain.
Animals—6 horses with right dorsal colon (RDC) fistulas.
Procedure—In a crossover design, horses were alternately
fed 1 of 3 diets: orchard grass hay ad libitum
after being adapted to this diet for at least 5 days,
orchard grass hay ad libitum and 4.55 kg of grain
offered every 12 hours after being adapted to orchard
grass hay ad libitum for at least 5 days, or orchard grass
hay ad libitum and 4.55 kg of grain offered every 12
hours after being adapted to this diet for at least 5 days.
Physical examinations were performed and samples of
blood, colonic contents, and feces were collected
every 6 hours during a 48-hour observation period.
Results—Grain ingestion had several effects, including
changes in the concentrations of electrolytes in plasma;
RDC contents became more homogenous, dehydrated,
foamy, and less dense; RDC contents flowed
spontaneously when the cannula was opened; RDC
contents expanded when heated in an oven; and feces
became fetid and less formed. Horses did not have any
clinical signs of colic, endotoxemia, or laminitis.
Conclusions and Clinical Relevance—Changes
observed in the colonic contents and feces may be
explained by the large amounts of hydrolyzable carbohydrates
provided by grain. Access to large
amounts of grain may increase the risk of tympany
and displacement of the large intestine. ( Am J Vet Res 2004;65:687–694)
Objective—To assess changes in systemic hydration,
concentrations of electrolytes in plasma, hydration of
colonic contents and feces, and gastrointestinal transit
in horses treated with IV fluid therapy or enteral
administration of magnesium sulfate (MgSO4), sodium
sulfate (NaSO4), water, or a balanced electrolyte
Animals—7 horses with fistulas in the right dorsal
Procedure—In a crossover design, horses alternately
received 1 of 6 treatments: no treatment (control); IV
fluid therapy with lactated Ringer's solution; or enteral
administration of MgSO4, Na2SO4, water, or a balanced
electrolyte solution via nasogastric intubation.
Physical examinations were performed and samples
of blood, RDC contents, and feces were collected
every 6 hours during the 48 hour-observation period.
Horses were muzzled for the initial 24 hours but had
access to water ad libitum. Horses had access to hay,
salt, and water ad libitum for the last 24 hours.
Results—Enteral administration of a balanced electrolyte
solution and Na2SO4 were the best treatments
for promoting hydration of RDC contents, followed by
water. Sodium sulfate was the best treatment for promoting
fecal hydration, followed by MgSO4 and the
balanced electrolyte solution. Sodium sulfate caused
hypocalcemia and hypernatremia, and water caused
Conclusions and Clinical Relevance—Enteral
administration of a balanced electrolyte solution promoted
hydration of RDC contents and may be useful
in horses with large colon impactions. Enteral administration
of either Na2SO4 or water may promote
hydration of RDC contents but can cause severe electrolyte
imbalances. (Am J Vet Res 2004;65:695–704)
Objective—To quantify peripheral blood neutrophil apoptosis in equine patients with acute abdominal disease (ie, colic) caused by strangulating or nonstrangulating intestinal lesions and compare these values with values for horses undergoing elective arthroscopic surgery.
Animals—20 client-owned adult horses.
Procedures—Peripheral blood was collected from horses immediately prior to and 24 hours after surgery for treatment of colic (n = 10) or elective arthroscopic surgery (10), and neutrophils were counted. Following isolation by means of a bilayer colloidal silica particle gradient and culture for 24 hours, the proportion of neutrophils in apoptosis was detected by flow cytometric evaluation of cells stained with annexin V and 7-aminoactinomycin D. Values were compared between the colic and arthroscopy groups; among horses with colic, values were further compared between horses with and without strangulating intestinal lesions.
Results—Percentage recovery of neutrophils was significantly smaller in preoperative samples (median, 32.5%) and in all samples combined (35.5%) for the colic group, compared with the arthroscopy group (median, 66.5% and 58.0%, respectively). No significant differences in the percentages of apoptotic neutrophils were detected between these groups. Among horses with colic, those with strangulating intestinal lesions had a significantly lower proportion of circulating apoptotic neutrophils in postoperative samples (median, 18.0%) than did those with nonstrangulating lesions (66.3%).
Conclusions and Clinical Relevance—The smaller proportion of apoptotic neutrophils in horses with intestinal strangulation suggested that the inflammatory response could be greater or prolonged, compared with that of horses with nonstrangulating intestinal lesions. Further investigations are needed to better understand the relationship between neutrophil apoptosis and inflammation during intestinal injury.
Objective—To estimate the national incidence of,
operation-level risk factors for, and annual economic
impact of colic among horses in the United States
during 1998 and 1999.
Animals—21,820 horses on 1,026 horse operations
in 28 states.
Procedures—Horses were monitored for colic for 1
year, and results were recorded in a log that was collected
quarterly. Operation-level data were collected
via 4 on-site personal interviews. Associations
between colic and independent variables adjusted for
size of operation were determined.
Results—Annual national incidence of colic in the US
horse population was estimated to be 4.2 colic
events/100 horses per year. Case fatality rate was
11%, and 1.4% of colic events resulted in surgery.
Annual cost of colic in the Unites States was estimated
to be $115,300,000.
Conclusions and Clinical Relevance—The national
impact of equine colic is substantial because of the
high case fatality rate. (J Am Vet Med Assoc 2001;
Objective—To identify apoptosis in equine intestines
and determine whether apoptosis is associated with
gastrointestinal tract disease or a specific tissue layer
Animals—38 horses that underwent surgery or were
euthanatized for small or large intestine obstruction,
strangulation, or distension and 9 control horses
euthanatized for reasons other than gastrointestinal
tract disease or systemic disease.
Procedure—Specimens were collected at surgery
from intestine involved in the primary lesion and distant
to the primary lesion site or at necropsy from
several sites including the primary lesion site.
Histologic tissue sections were stained with H&E,
and apoptosis was detected by use of the terminal
deoxynucleotidyl transferase-mediated dUTP nick end
labeling technique. The number of apoptotic cells per
hpf was counted in the mucosa, circular muscle, longitudinal
muscle, and serosa.
Results—Apoptotic nuclei were seen in all layers of
intestine. An increased number of apoptotic cells was
found in the circular muscle of the intestine from horses
with simple obstruction, compared with strangulating
obstruction or healthy intestine. Intestine distant
from a primary strangulating lesion had higher numbers
of apoptotic cells than did intestine distant from
a simple obstructive lesion or intestine taken at the
site of a strangulating or simple obstructive lesion.
Conclusions and Clinical Relevance—Intestine
from horses with obstructing or strangulating lesions
in the small intestine and large colon had high numbers
of apoptotic cells possibly because of ischemic
cell injury and subsequent inflammation. Whether
substantial apoptosis affects intestinal function is not
yet known. (Am J Vet Res 2003;64:982–988)