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 determine history; clinical, radiographic, ultrasonographic, and scintigraphic abnormalities; treatment; and outcome in horses with tuber coxae fractures and to describe a useful technique for obtaining a dorsomedial-ventrolateral 50° oblique radiographic view of the tuber coxa of the ilium in standing horses.
Design—Retrospective case series.
Animals—29 horses with fractures of tuber coxa.
Procedures—Data collected from medical records included signalment; history; horse use; severity and duration of lameness; radiographic, ultrasonographic, and scintigraphic findings; treatment; and outcome.
Results—All horses had a traumatic event leading to acute, unilateral hind limb lameness. Eighteen horses had a more severe lameness at the walk than at the trot; 22 of 29 horses had an abnormal gait with the hind limbs tracking to 1 side of the forelimbs. Twenty-four of 29 horses had palpable and visual asymmetry between the affected and unaffected tuber coxae. Twenty horses had radiography performed while sedated but standing, and fractures were reliably identified on the dorsomedial-ventrolateral 50° oblique radiographic views. Twenty-seven (27/29 [93%]) horses returned to athletic use. Horses sustaining partial fractures of the caudal aspect of tuber coxae returned to previous use significantly earlier (mean, 3 months), compared with horses with complete tuber coxae fractures (6.5 months).
Conclusions and Clinical Relevance—Horses with tuber coxae fractures returned to athletic soundness following extended periods of rest. Findings emphasized the need for obtaining a dorsomedial-ventrolateral 50° oblique radiographic view of the tuber coxa of the ilium in horses suspected of sustaining injury to this region.
Case Description—4 horses with enthesopathy and desmitis of the medial collateral ligament of the cubital joint were examined.
Clinical Findings—All 4 horses had a history of acute, severe, unilateral forelimb lameness and had signs of pain during manipulation of the affected upper forelimb; 2 also had swelling in the axillary region. There was no improvement in lameness after diagnostic local analgesia below the carpal region, and 1 of 4 horses had mild improvement after cubital joint analgesia. Radiography revealed enthesophyte formation on the radial tuberosity and linear mineralization of the medial collateral ligament in 2 horses and periosteal reaction on the humeral condyle in all 4 horses. One horse had mild osteoarthritis of the cubital joint, and 3 had osteophytosis of the cranial aspect of the radius. Although all horses were initially examined because of an acute onset of lameness, all had chronic abnormalities visible on imaging. Ultrasonography revealed an irregular boney contour and enthesopathy at the insertion of the short medial collateral ligament to the radial tuberosity and desmitis of the short medial collateral ligament. Two horses had radiographic evidence of similar but less severe lesions of the contralateral cubital joint.
Treatment and Outcome—All horses received phenylbutazone and rest. All horses were free of lameness after a median of 3 months (range, 2 to 4 months) and returned to previous use after a median of 6 months (range, 3 to 8 months).
Conclusions and Clinical Relevance—The results of the present report suggested that performance horses with enthesopathy and desmitis of the medial collateral ligament of the cubital joint may have a good prognosis for return to previous use following appropriate treatment.
Objective—To determine history, clinical and radiographic
abnormalities, and outcome in horses with
signs of navicular area pain unresponsive to corrective
shoeing and systemic nonsteroidal anti-inflammatory
drug administration that were treated with an injection
of corticosteroids, sodium hyaluronate, and
amikacin into the navicular bursa.
Procedure—Data collected from the medical records
included signalment, history, horse use, severity and
duration of lameness, shoeing regimen, results of
diagnostic anesthesia, radiographic abnormalities,
Results—17 horses had bilateral forelimb lameness,
7 had unilateral forelimb lameness, and 1 had unilateral
hind limb lameness. Mean duration of lameness
was 9.2 months. All horses had been treated with
corrective shoeing and nonsteroidal anti-inflammatory
drugs for at least 6 months; 18 had previously been
treated by injection of corticosteroids and sodium
hyaluronate into the distal interphalangeal joint.
Fourteen horses had mismatched front feet, and 21
horses had signs of pain in response to application of
pressure over the central aspect of the frog. Palmar
digital nerve anesthesia resulted in substantial
improvement in or resolution of the lameness in all
horses. Twenty horses (80%) were sound and
returned to intended activities 2 weeks after navicular
bursa treatment; mean duration of soundness was
4.6 months. Two horses that received numerous navicular
bursa injections had a rupture of the deep digital
flexor tendon at the level of the pastern region.
Conclusions and Clinical Relevance—Results suggest
that navicular bursa treatment may provide temporary
improvement in horses with signs of chronic
navicular area pain that fail to respond to other treatments.
(J Am Vet Med Assoc 2003;223:1469–1474)
Objective—To determine clinical history, structures
involved, treatment, and outcome of lacerations of
the heel bulb and proximal phalangeal region (pastern)
Procedures—Medical records of horses with lacerations
of the heel bulb and pastern were reviewed, and
follow-up information was obtained.
Results—75 horses were Quarter Horses. Most
horses were not treated with antimicrobial drugs prior
to referral. Mean ± SD time from injury to referral was
24 ± 45 hours (range, 1 to 168 hours). Lacerations
were most frequently caused by contact with wire or
metal objects. In 17 horses, lacerations involved synovial
structures; the distal interphalangeal joint was
most commonly affected. One horse was euthanatized
after initial examination. Wound treatment consisted
of cleansing, lavage, debridement, lavage of
affected synovial structures, suturing of fresh
wounds, and application of a foot bandage or cast.
Fifty-six horses were treated with systemically administered
antimicrobial drugs. Follow-up information
was collected for 61 horses. Fifty-one horses returned
to their intended use and had no further complications;
10 horses had complications associated with
the wound, and of those horses, 5 were euthanatized
and 1 horse died from an unrelated cause. Horses
with lacerations that involved synovial structures had
worse outcomes than horses with lacerations that did
not involve synovial structures.
Conclusions and Clinical Relevance—Horses that
sustain heel bulb lacerations can successfully return
to their intended use. Involvement of the distal interphalangeal
joint is associated with poor prognosis.
(J Am Vet Med Assoc 2005;226:418–423)
Objective—To evaluate effects of Carolina rinse solution,
dimethyl sulfoxide (DMSO), and 21-aminosteroid,
U-74389G, on microvascular permeability and
morphology of the equine jejunum after low-flow
ischemia and reperfusion.
Animals—20 healthy adult horses.
Procedure—Under anesthesia, full-thickness biopsy
specimens of a distal portion of the jejunum were
obtained for baseline measurements. In addition to a
control segment, 2 jejunal segments were identified
as sham-operated or experimental segments.
Experimental segments underwent 60 minutes of
low-flow ischemia and 3.5 hours of reperfusion.
Treatments were as follows: U-74389G (3 mg/kg, IV; 6
horses), DMSO (20 mg/kg, IV; 6) diluted in 1 L of saline
(0.9% NaCl) solution, local perfusion (via jejunal artery)
of Carolina rinse solution (0.5 mL/kg; 4), and local perfusion
of lactated Ringer's solution (0.5 mL/kg; 4).
Results—Jejunal microvascular permeability was
significantly lower after treatment with Carolina rinse
solution or DMSO, compared with U-74389G or lactated
Ringer's solution treatments. After DMSO
treatment, serosal- and submucosal-layer edema
was significantly increased in experimental segments,
compared with control or sham-operated
segments; however, edema increases were significantly
less than for lactated Ringer's solution or
U-74389G treatments. Significant decreases in
intestinal wet weight-to-dry weight ratio were found
following Carolina rinse solution or DMSO treatments,
compared with lactated Ringer's solution or
U-74389G treatments. Edema formation and leukocyte
infiltration in jejunal segments of horses treated
with lactated Ringer's solution or U-74389G were
increased, compared with Carolina rinse solution or
Conclusions and Clinical Relevance—Carolina rinse
solution and DMSO may be protective against
ischemia-reperfusion injury in the equine jejunum.
(Am J Vet Res 2005;66:525–536)
Objective—To determine clinical and radiographic abnormalities in and outcome of horses with fractures of the greater tubercle of the humerus and to develop a radiographic technique for obtaining a cranioproximal-craniodistal oblique projection of the proximal portion of the humerus in standing horses.
Design—Retrospective case series.
Procedures—Data collected from medical records included signalment, history, horse use, severity and duration of lameness, radiographic and ultrasonographic findings, treatment, and outcome.
Results—All horses had a history of acute, unilateral lameness. Twelve of 15 had visual or palpable abnormalities in the shoulder region. In 6 of 8 horses, the fracture could be seen on a cranioproximal-craniodistal projection of the proximal portion of the humerus. In 2 horses, this was the only projection on which the fracture could be seen, and in an additional 2, this was the projection on which the fracture could be seen most reliably. Ten horses underwent surgery (fragment removal, 7; open reduction and internal fixation, 2; and exploration without fragment removal, 1), and 5 were treated with variable periods of stall rest and turnout. Eleven horses returned to athletic use, including 9 of the 10 treated surgically and 2 of the 5 treated without surgery.
Conclusions and Clinical Relevance—Results suggested that horses with fractures of the greater tubercle of the humerus can return to athletic soundness following treatment and emphasized the need for obtaining a cranioproximal-craniodistal radiographic projection of the proximal portion of the humerus in horses suspected to have an injury in this region.
Objective—To determine clinical, radiographic, and
scintigraphic abnormalities in and outcome of horses
with septic or nonseptic osteitis of the axial border of
the proximal sesamoid bones.
Procedure—Data collected from medical records
included signalment; history; horse use; severity and
duration of lameness; results of perineural anesthesia,
radiography, ultrasonography, and scintigraphy;
and outcome following surgery.
Results—Five horses did not have any evidence of
sepsis; the other 3 had sepsis of the metacarpophalangeal
or metatarsophalangeal joint or the digital synovial
sheath. All horses had a history of chronic unilateral
lameness. Three of 5 horses improved after
diagnostic anesthesia of the metacarpophalangeal or
metatarsophalangeal joint; the other 2 improved only
after diagnostic anesthesia of the digital synovial
sheath. Nuclear scintigraphy was beneficial in localizing
the source of the lameness to the proximal
sesamoid bones in 4 horses. Arthroscopy of the palmar
or plantar pouch of the joint or of the digital synovial
sheath revealed intersesamoidean ligament
damage and osteomalacia of the axial border of the
proximal sesamoid bones in all horses. All 5 horses
without sepsis and 1 horse with sepsis returned to
their previous uses.
Conclusions and Clinical Relevance—Results suggest
that osteitis of the axial border of the proximal
sesamoid bones is a distinct entity in horses that typically
is associated with inflammation of the associated
metacarpointersesamoidean or metatarsointersesamoidean
ligament and may be a result of sepsis or
nonseptic inflammation. Arthroscopic debridement
may allow horses without evidence of sepsis to
return to their previous level of performance. (J Am
Vet Med Assoc 2001;219:82–86)