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 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 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 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 determine effects on anal pressure of
horses after local injection of the external anal sphincter
with Clostridium botulinum toxin type B.
Animals—11 healthy adult horses.
Procedure—Peak and resting anal sphincter pressures
were measured with a custom-made rectal
probe that was connected to a pressure transducer.
Pressures were measured before treatment and after
injection with botulinum toxin type B (BTB) or saline
(0.9% NaCl) solution. Dose titration with 500, 1,000,
1,500, and 2,500 U of BTB was completed. Physical
changes, behavior, and anal pressure were recorded
for each horse.
Results—Injection of 1,000 U of BTB caused a significant
reduction in peak anal pressure from days 2 to
84, compared with pressure in control horses.
Maximal effect of the toxin was observed within the
first 15 days after injection, followed by a slow return
to baseline during the 168-day period. Injection of
2,500 U of BTB in the anal sphincter in 1 horse resulted
in lethargy, generalized weakness, and dysphagia
for 14 days. Adverse clinical effects were not
observed in horses after injections with 500, 1,000, or
1,500 U of BTB.
Conclusions and Clinical Relevance—The effect of
focal intramuscular injection of BTB in horses is similar
to that reported for other species. However, horses
appear to be more sensitive to BTB, compared
with other species, and clinical signs of botulism may
develop at doses exceeding 1,500 U. Injections of
BTB in the external anal sphincter of mares may be
useful to reduce incisional dehiscence after repair of
perineal lacerations. ( Am J Vet Res 2004;65:26–30)
Objective—To identify the types of injuries sustained
by horses that competed in steeplechase races and
determine the prevalence of and risk factors for those
Animals—2,680 horses that competed in various
types of steeplechase races from 1996 through 2000.
Procedure—Data regarding races; environment;
equipment problems; the number of horses that
entered, started, and finished races; the number of
riders that fell; and the number of horses that were
slowed or stopped by the rider, ran off the course, fell,
and sustained injuries or physical abnormalities during
races were collected on a standard form by the official
veterinarian who attended each meet. Data from
all meets were not recorded; however, in recorded
meets, data from every race were reported.
Results—Data for 197 hurdle, 65 timber, 76 flat, and
8 mixed races were recorded. Nine (3.4/1,000 horses
that started in races) horses died or were euthanatized,
and 7 of those were associated with catastrophic
musculoskeletal injury. Seven fractures were
recorded. Four fractures involved forelimbs, 1
involved a hind limb, and 2 involved the cervical portion
of the vertebral column. All horses with fractures
were euthanatized. Deep or hard course conditions
were associated with an increased risk of breakdown
Conclusions and Clinical Relevance—Successful
development and implementation of strategies to
prevent injuries and death in horses in steeplechase
races depend on a clear understanding of the types
and prevalence of injuries involved and risk factors
associated with those injuries. (J Am Vet Med Assoc
Objective—To determine the safety and short-term efficacy of intrabursal administration of botulinum toxin type B (BTXB) to alleviate lameness in horses with degenerative injury to the podotrochlear apparatus (PA).
Animals—10 Quarter Horses with degenerative injury to the PA.
Procedures—Degenerative injury to the PA was confirmed with diagnostic analgesia and imaging. Then, BTXB (3.8 to 4.5 U/kg) was injected into the podotrochlear (navicular) bursa of each horse. Three horses were used in a safety evaluation. Subsequently, video recordings of lameness evaluations were obtained for 7 client-owned horses 5 days before (baseline) and 7 and 14 days after BTXB treatment and used to determine the effect of BTXB injection on lameness; 1 horse was removed from the study 8 days after BTXB treatment. Three investigators who were unaware of the treated forelimbs or time points separately reviewed the recordings and graded the lameness of both forelimbs of the horses.
Results—Improvement in lameness of the treated forelimbs was detected at 1 or both time points after BTXB administration in all horses. However, all horses had some degree of lameness at the end of the study. Two horses developed transient increases in lameness 48 to 72 hours after treatment; lameness resolved uneventfully.
Conclusions and Clinical Relevance—Intrabursal injection of BTXB temporarily alleviated chronic lameness in horses with degenerative injury to the PA, without causing serious short-term adverse effects. Further investigation into the potential use of BTXB in horses affected by degenerative injury to the PA is warranted.