Exercise intolerance and poor performance in western performance and sprint horses.

This article deals with the presenting histories, clinical examinations, and therapies of the causes of poor performance and exercise intolerance in the western performance horse and the sprint racehorse. The veterinarian's ability to diagnose and treat various pathophysiologic conditions that affect these horses is crucial to the major goals of a return to optimal performance and a long athletic career. Although these horses are a significant portion of most veterinary practices, there exists a minimal amount of information on their clinical evaluation and treatment. This article intends to fill this void.

Treatment of a comminuted frontal-plane fracture of the distal phalanx in a horse.

Successful treatment of a comminuted frontal plane fracture of the distal phalanx in a horse is described. The bone fractured through the solar canal, close to the insertion of the deep digital flexor tendon. A hoof case was used to reduce bending and tensile stresses on the solar surface by limiting expansion of the hoof wall during weightbearing. In addition, the heel was elevated, using 3 degrees wedge pads incorporated within the hoof cast, to reduce distraction at the fracture site caused by the pull of the deep digital flexor tendon. Two casts were used over a 4-month period. Complete radiographic healing of the fracture was evident 4 months after injury. At this time the horse was lame at the trot. The owner reported the horse to be sound 7 months after injury. Reexamination 12 months after injury revealed a clinically normal foot and no lameness.

Correction of patellar luxation by recession sulcoplasty in three foals.

Lateral luxation of the patella in four femoropatellar joints of three foals was repaired by recession sulcoplasty and medial imbrication of the joint. One foal was euthanatized because of septic arthritis caused by incisional dehiscence, and the other two foals were normal 2 years after surgery. Recession sulcoplasty combined with medial imbrication of the joint capsule resulted in a functional femoropatellar joint and should be considered in foals affected with lateral patellar luxation.

Fecalith impaction in four miniature foals.

Four miniature foals admitted with signs of progressive nonresponsive abdominal pain and no fecal production had fecalith impaction of the small colon. Duration of clinical signs ranged from 10 hours to 5 days. Removal of the fecalith via small colon enterotomy was a successful treatment in all 4 cases. Miniature foals may be predisposed to fecalith impaction of the small colon. If a miniature foal has signs of progressive nonresponsive abdominal pain, fecalith impaction needs to be considered. Surgical correction may be required.

Monitoring surface conditions of a Thoroughbred racetrack.

During a pilot study at a Thoroughbred racetrack, information was collected to include weather conditions and track surface properties (moisture content, composition, strength, and coefficient of friction between surface and hoof). Measured weather variables did not correlate to any pattern of horse injuries of breakdowns. Surface moisture content was variable, whereas the moisture content of the compacted cushion was constant. Track surfaces around the starting chutes were more compacted than were other areas of the track. Next to the rail, track surface was softer than the surface toward the middle of the track. The coefficient of friction between a hoof and the surface was not affected by location or surface moisture content.

Displacement of the large colon associated with nonsurgical correction of large-colon entrapment in the renosplenic space in a mare.

Nonsurgical correction of a renosplenic entrapment of the large colon was attempted in a mare, using a rolling technique. After correction, the mare had initial improvement in clinical signs, but later developed signs of abdominal discomfort. A ventral midline celiotomy was performed, and a pelvic flexure impaction and large intestinal volvulus were found and corrected.

Factors affecting incisional complication rates associated with colic surgery in horses: 78 cases (1983-1985).

From May 1, 1983 to April 1, 1985, 142 operations were performed on horses with signs of acute abdominal pain (colic), using a ventral midline incision. Seventy-eight horses lived for at least 15 days after surgery or had acute dehiscence and were included in the study. Seventy horses had surgery once, and 8 horses had surgery 2 or more times. Six-month follow-up evaluation was obtained for 66 horses that had 1 surgery and for 6 horses that had multiple surgeries. Incisional complications included drainage (including infection), acute dehiscence, hernia, and suture sinus formation. The effects of preoperative peritoneal fluid presence, enterotomy or resection, suture material and pattern used in the linea alba, type of skin closure and use of a sutured-on stent bandage on the incidence of incisional complications were investigated. The complication of incisional infection rate associated with a near-far-far-near suture pattern vs simple interrupted pattern in the linea alba was the only statistically significant (P less than 0.05) difference observed.

Use of high-speed cinematography and computer generated gait diagrams for the study of equine hindlimb kinematics.

High-speed cinematography with computer aided analysis was used to study equine hindlimb kinematics. Eight horses were filmed at the trot or the pace. Filming was done from the side (lateral) and the back (caudal). Parameters measured from the lateral filming included the heights of the tuber coxae and tailhead, protraction and retraction of the hoof and angular changes of the tarsus and stifle. Abduction and adduction of the limb and tarsal height changes were measured from the caudal filming. The maximum and minimum values plus the standard deviations and coefficients of variations are presented in tabular form. Three gait diagrams were constructed to represent stifle angle versus tarsal angle, metatarsophalangeal height versus protraction-retraction (fetlock height diagram) and tuber coxae and tailhead height versus stride (pelvic height diagram). Application of the technique to the group of horses revealed good repeatability of the gait diagrams within a limb and the diagrams appeared to be sensitive indicators of left/right asymmetries.

Intramural hematoma in the jejunum of a mare.

An intramural hematoma involving a 40-cm segment of the distal portion of the jejunum caused intestinal obstruction and colic in a mature mare. The involved intestine was resected, and an end-to-end anastomosis was performed. The mare recovered completely, but 4 years later had colic caused by incarceration and volvulus of the distal portion of the jejunum, involving fibrous abdominal adhesions. The cause of hematoma was not identified; however, rupture of an intramural vessel after migration of Strongylus vulgaris larvae was considered a possibility because of the histologic observation of an intense eosinophilic infiltrate in the region. Vascular rupture caused by blunt abdominal trauma was considered unlikely. Previous descriptions of intramural hematoma in the horse have been confined to the small colon.