Electrohydraulic Shockwave for Treatment of Forelimb Superficial Digital Flexor Tendinitis and Proximal Suspensory Desmitis in Horses.

Superficial digital flexor tendinitis (SDFT) and proximal suspensory desmitis (PSD) are common causes of lameness in horses. Current treatment options include rest, controlled exercise, administration of anti-inflammatories, intralesional injections, surgery, and electrohydraulic shock wave therapy (ESWT). ESWT is safe, noninvasive, and is used to treat a variety of musculoskeletal abnormalities. Medical records between 2010 and 2021 were reviewed. Horses were separated into two categories: (group 1: ≥ 3 ESWT treatments; group 2: < 3 ESWT treatments). Our objective was to examine the effect of the number of ESWT treatments in the management of SDFT and PSD injuries and to compare short- and long-term outcomes for the two groups. For group 1, lameness scores between the first and third treatments were significantly reduced in both PSD (P < .0001) and SDFT (P = .016) horses. However, neither the PSD (P = .062) nor SDFT's (P = .125) ultrasound findings were significantly different at the end of the third treatment. Horses with PSD showed a significant improvement in forelimb lameness between the first and third treatments compared to hindlimb (P = .033). In the multivariable ordered logistic regression model, only time (months of follow-up) was significantly associated with a positive outcome (P = .001) and there was no difference in short and long-term outcome between groups 1 and 2. Also, chronicity of injury was negatively associated with improvement of lameness (P = .028).

Treatment of shoulder joint luxation with glenoid ostectomy in a miniature donkey.

CASE DESCRIPTION: A 13-year-old 128-kg miniature donkey gelding was evaluated for right forelimb lameness of 7 weeks' duration. CLINICAL FINDINGS: Muscular atrophy of the infraspinatus and supraspinatus muscles over the right scapula with a palpable bony prominence over the point of the shoulder was evident. At the walk, the cranial phase of the stride was reduced with adduction of the distal aspect of the limb, dragging of the toe, and lameness (grade, 4/5). Lateral and craniocaudal radiographs of the right shoulder joint revealed lateral luxation of the humerus in relation to the scapula with bony proliferation and remodeling of the humeral head. TREATMENT AND OUTCOME: Glenoid ostectomy was performed. Immediately after surgery, the donkey was able to intermittently stand squarely on the limb but maintained a reduced cranial phase of the stride at the walk. The donkey had no short-term complications and was discharged from the hospital 11 days after surgery. Following discharge, the donkey was confined to a box stall for 60 days, followed by a gradual increase in movement to full pasture turnout. The lameness continued to improve, and at 15 months after surgery the donkey was turned out in pasture and had mild lameness (grade, 3/5) at the trot. Mild muscular atrophy of the supraspinatus and infraspinatus muscles was present with no signs of pain on palpation or manipulation of the limb. Shoulder joint radiography at 15 months after surgery revealed remodeling of the glenoid cavity of the scapula and humeral head with formation of a pseudoarthrosis. CLINICAL RELEVANCE: Glenoid ostectomy should be considered as an alternative to shoulder joint arthrodesis in small equids with shoulder joint luxation. Other indications for this procedure could include chronic osteoarthritis or fractures affecting the shoulder joint.

Cryptorchidectomy with a paramedian or inguinal approach in domestic pigs: 47 cases (2000-2018).

OBJECTIVE: To describe cryptorchidectomy performed with a paramedian or inguinal approach in domestic pigs and compare findings for commercial-breed pigs with those for pot-bellied pigs. ANIMALS: 47 client-owned (33 commercial-breed and 14 pot-bellied) pigs. PROCEDURES: Medical records were searched to identify pigs that underwent surgical treatment for cryptorchidism from 2000 to 2018. Signalment, location of retained testes, surgeon, surgical approach, surgery time, anesthesia time, and postoperative complications were recorded. Complications were assessed with long-term follow-up. Age and surgical variables were compared between commercial-breed pigs and pot-bellied pigs. RESULTS: Retained testes were most commonly located in the abdomen (27/47 [57%] left-sided, 15/47 [32%] right-sided, and 2/47 [4%] bilateral); 2 pigs each had 1 retained testis in the inguinal region, and 1 pig had 1 retained testis in the abdomen and 1 in the inguinal region. Forty-four pigs with abdominally retained testes were treated successfully with a paramedian surgical approach, including 3 for which an inguinal approach was attempted first. An inguinal approach was successful for 3 pigs with inguinally retained testes and 1 with an abdominally retained testis. Standard castration techniques were used for normally descended and inguinally retained testes. Long-term follow-up was available for 34 pigs; minor complications were reported for 3 (9%). Pot-bellied pigs were significantly older than commercial-breed pigs. No other intergroup differences were found. CONCLUSIONS AND CLINICAL RELEVANCE: The paramedian surgical approach was successfully used for removal of abdominally retained testes in all pigs that underwent the procedure. The overall complication rate for cryptorchidectomy in the study sample was low.

Mastectomy in 25 small ruminants (2002-2019).

OBJECTIVE: To describe the outcome of small ruminants treated with unilateral and bilateral mastectomy by using three surgical techniques. STUDY DESIGN: Retrospective study. ANIMALS: Twenty-five small ruminants (24 goats and one sheep). METHODS: Medical records of animals that underwent mastectomy between November 1, 2002, and May 1, 2019, were reviewed. Follow-up information was obtained by telephone questionnaire with owners. Signalment, surgical data, intraoperative and postoperative complications, bacterial culture results, histopathologic diagnoses, short- and long-term outcomes, and other procedures performed were recorded. RESULT: Procedures consisted of six unilateral (with an elliptical incision) and 19 total (with inverted cloverleaf or elliptical skin incisions) mastectomies. All animals survived to hospital discharge. Intraoperative complications included contamination of the surgical site with mammary-gland fluid, hemorrhage, and difficulty dissecting skin from the mammary gland. Postoperative complications included seroma formation (7/25), surgical-site infection (5/25), and dehiscence of the skin incision (3/25). Mammary neoplasia was diagnosed in seven of 15 animals with histopathologic examination. No association was detected between surgical technique, diagnosis of neoplasia, and long-term outcome. Overall, client satisfaction was high. CONCLUSION: Mastectomy was effective at removing abnormally enlarged udders secondary to chronic mastitis, inappropriate lactation, idiopathic causes, or neoplasia and was associated with a low rate of complications in small ruminants. CLINICAL SIGNIFICANCE: Unilateral mastectomy with an elliptical skin incision or total mastectomy, preferably with inverted cloverleaf skin incision, may be indicated to remove diseased mammary tissue in small ruminants and can result in long-term survival with low morbidity and cosmetically pleasing results.

Caudal paramedian approach to cryptorchidectomy in 29 small ruminants (2011-2019).

OBJECTIVE: To describe a caudal paramedian approach to cryptorchidectomy in small ruminants. STUDY DESIGN: Retrospective case series. ANIMALS: Sheep (n = 20) and goats (n = 9) with cryptorchidism. METHODS: Medical records from January 2011 to July 2019 of small ruminants that underwent caudal paramedian cryptorchidectomy at our institution were retrospectively reviewed. Data from animal signalment, operative and postoperative complications, and client satisfaction were evaluated. RESULTS: Twenty sheep and nine goats underwent caudal paramedian cryptorchidectomy during the study period. The median age of rams was 2 months, and the median age of bucks was 3 months; median weights for rams and bucks were 20.5 kg (range, 14.5-41.3) and 28.1 kg (range, 12.9-82), respectively. Cryptorchidism was bilateral in 27.6% (8/29) of cases and unilateral in 72.4% (21/29). Among unilateral cases, 85.7% (18/21) were right sided and 14.3% (3/21) were left sided. Twenty-four of 29 (82.8%) cases were performed under sedation. One operative complication occurred in a 4-year-old 82 kg buck (rate, 3.4% [95% CI: 0.1%-17.2%]). Postoperatively, there were two minor and one major complications (rates, 6.9% [95% CI: 0.8%-22.1%] and 3.4% [95% CI: 0.1%-17.2%], respectively). Long-term follow-up (range, 8-117 months) reports described owner satisfaction and all animals doing well at the time of follow-up telephone call. CONCLUSION: Caudal paramedian approach to cryptorchidectomy was safely performed in small ruminants less than 4 months old. CLINICAL SIGNIFICANCE: Ease of surgical technique, minimal operative and postoperative complications, and owner satisfaction make this a suitable method for cryptorchidectomy.

Comparison of the racing performance of Thoroughbreds with versus without osteochondral fragmentation of the accessory carpal bone identified on yearling sales repository radiographs.

OBJECTIVE To evaluate 2- and 3-year-old and career race performance of Thoroughbred racehorse prospects with and without osteochondral fragmentation of the accessory carpal bone (ACB) identified on yearling presale radiographs. DESIGN Retrospective, matched cohort study. ANIMALS 47 nonlame Thoroughbreds with (exposed cohort) and 94 nonlame Thoroughbreds without (unexposed cohort) osteochondral fragmentation of ACB facture identified on yearling sales repository radiographs. PROCEDURES Repository radiographic interpretation reports for September yearling sales of a large Kentucky auction house from 2005 through 2012 were reviewed, and race records were collected and analyzed. Race performance was compared between horses with and without ACB fracture chosen from the same sale to identify associations between racing performance and ACB fracture. RESULTS No significant differences were identified between horses with or without ACB fracture in their incidence of starting a race as a 2- or 3-year-old and the number of races started, earnings, or earnings per start for 2- or 3-year-old or career race performance. There was no significant difference in performance between horses with or without concurrent carpal osteoarthritis, nor did performance differ between horses with ACB fracture alone and those with ACB fracture and other radiographic abnormalities found to be associated with poorer performance in previous studies. CONCLUSIONS AND CLINICAL RELEVANCE ACB fracture with or without carpal osteoarthritic changes identified on repository radiographs of Thoroughbred yearlings was not associated with poorer racing performance or lower likelihood of starting a race as a 2- or 3-year-old, compared with outcomes for unaffected horses.

Comparison of omentopexy versus pyloro-omentopexy for treatment of left abomasal displacement in dairy cows: 87 cases (2001-2005).

OBJECTIVE To evaluate reproductive performance and productive longevity of dairy cows treated for left displaced abomasum (LDA) with 1 of 2 surgical techniques (omentopexy vs pyloro-omentopexy). DESIGN Retrospective case series. ANIMALS 87 Holstein cows that underwent omentopexy or pyloro-omentopexy for LDA during a 5-year period. PROCEDURES For each cow with LDA, the most recent date of calving, age at time of surgery, and surgical procedure were recorded. Dairy records of cows treated for LDA in the 5-year period were reviewed to determine their reproductive performance. Records available for up to 4 years after the last surgery (ie, when all treated cows had left the herd) were reviewed to determine cull dates and reasons for treated and untreated cows in the herd. RESULTS Of the 87 cows with LDA, 58 underwent pyloro-omentopexy and 29 underwent omentopexy. Cows in the 2 treatment groups did not significantly differ in age. Fifty-six cows completed > 1 subsequent lactation cycle after surgery. The median time that cows with LDA remained in the herd was 566 days (range, 24 to 1,838 days); the times for the 2 treatment groups did not significantly differ. For treated and untreated cows, cull rates for reproductive failure or other problems were similar. Four (14%) omentopexy-treated cows and no pyloro-omentopexy-treated cows had a reoccurrence of LDA. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that cows with LDA that underwent omentopexy or pyloro-omentopexy had similar cull rates and reasons as unaffected herd mates over their productive time in the herd. Between the 2 treatment groups, only the LDA reoccurrence rate differed.

Effects of topical application of silver sulfadiazine cream, triple antimicrobial ointment, or hyperosmolar nanoemulsion on wound healing, bacterial load, and exuberant granulation tissue formation in bandaged full-thickness equine skin wounds.

OBJECTIVE To determine the effects of 3 topically applied treatments (1% silver sulfadiazine cream [SSC], triple antimicrobial ointment [TAO], and hyperosmolar nanoemulsion [HNE]) on microbial counts, exuberant granulation tissue (EGT) development, and reepithelialization of contaminated wounds at the distal aspect of the limbs of horses. ANIMALS 8 healthy adult horses. PROCEDURES A 2.5 × 2.5-cm, full-thickness, cutaneous wound was created at the dorsal aspect of each metacarpus and metatarsus (1 wound/limb/horse), covered with nonadhesive dressing, and bandaged. Wounds were inoculated with bacteria and fungi the next day. Each wound on a given horse was randomly assigned to 1 of 4 treatment groups (SSC, TAO, HNE, or no topical treatment [control]). Bandage changes, culture of wound samples, treatments, photography for wound measurements, and biopsy were performed at predetermined time points. Time (days) until wound closure, number of EGT excisions, microbial counts, and scores for selected histologic characteristics were compared among groups. RESULTS Median time to wound closure for all groups was 42 days. Time to wound closure and histologic characteristics of wound healing did not differ among groups. Least squares mean microbial counts were significantly higher for HNE-treated wounds on days 9 and 21, compared with SSC-treated and TAO-treated wounds, but not controls. Proportions of SSC-treated (7/8) or HNE-treated (5/8) wounds needing EGT excision were significantly greater than that of TAO-treated (1/8) wounds. The proportion of SSC-treated wounds with EGT excision was greater than that of controls (3/8). CONCLUSIONS AND CLINICAL RELEVANCE None of the treatments resulted in more rapid wound closure, compared with that for untreated control wounds under the study conditions. When treatment is warranted, TAO may help to limit EGT formation.

Cryptorchidectomy in equids: 604 cases (1977-2010).

OBJECTIVE: To evaluate the management of equids undergoing cryptorchidectomy at a referral hospital. DESIGN: Retrospective case series. ANIMALS: 604 client-owned equids. PROCEDURES: Medical records of all equids undergoing surgical treatment of cryptorchidism from 1977 to 2010 were retrospectively reviewed. Analyses of breed, location of retained testes, accuracy of palpation per rectum for determining the location of retained testes, surgical technique, and postoperative complications were performed. RESULTS: The most frequently affected breed was the Quarter Horse (282/604 [47%]), which was significantly overrepresented. Of the 604 equids, 90 (15%) had undergone previous surgical attempts at castration. Preoperative palpation per rectum was performed in 395/604 (65.4%) patients, and was accurate in predicting the location of the retained testes in 354/395 (89.6%). Surgeons were significantly more likely to be incorrect in determining the location of the retained testis by means of palpation per rectum in patients that had undergone a prior attempt at castration. For equids with abdominal cryptorchidism (360/604 [59.6%]), the most common surgical technique was noninvasive cryptorchidectomy (298/360 [82.8%]). In unilateral cryptorchids (521/604 [86.3%]), the 2 most common sites were left abdominal (184/521 [35.3%]) and right inguinal (148/521 [28.4%]). For bilateral retention (80/604 [13.2%]), abdominal cryptorchidism was most common (48/80 [60%]). Fever was present in 138/324 (43%) equids on the first day after surgery. Postoperative fever was not significantly associated with any variables evaluated. Including postoperative (≤ 24 hours) fever, 150 of 604 (25%) patients developed postoperative complications. Excluding postoperative fever, 18 of 604 (3%) patients developed major postoperative complications; complications in 10 of 604 patients were deemed surgically related, and 3 of 604 patients died. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that cryptorchidectomy in equids performed with a variety of surgical approaches was associated with minimal postoperative complications. A history of previous attempts at castration decreased the ability to accurately predict the location of the retained testis.

Comparison of hydroxyapatite-coated and uncoated pins for transfixation casting in horses.

OBJECTIVE: To determine the extent to which a hydroxyapatite coating promotes pin stability in the third metacarpal bone during transfixation casting in horses. ANIMALS: 14 adult horses. PROCEDURES: 7 horses each were assigned to either an uncoated or hydroxyapatite-coated pin group. Three transcortical pins were placed in the third metacarpal bone of each horse and incorporated into a cast for 8 weeks. Insertion and extraction torque were measured, and torque reduction was calculated. Radiography was performed at 0, 4, and 8 weeks. Lameness evaluation was performed at 2, 4, 6, and 8 weeks. Bacteriologic culture of pins and pin holes was performed at pin removal. RESULTS: All horses used casts without major complication throughout the study. Insertion torque was higher in uncoated pins. There was no effect of group on extraction torque. Hydroxyapatite-coated pins had lower torque reduction. Five of 15 hydroxyapatite-coated pins maintained or increased stability, whereas all uncoated pins loosened. Pin hole radiolucency, lameness grades, and positive bacteriologic culture rates were not different between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Hydroxyapatite coating increased pin stability within the third metacarpal bone of horses during 8 weeks of transfixation casting but did not improve pin performance on clinical assessments. Clinical use of hydroxyapatite-coated transfixation pins may result in greater pin stability; however, further research is necessary to improve the consistency of pin osteointegration and elucidate whether clinical benefits will ultimately result from this approach in horses.

Wooden, metallic, hair, bone, and plant foreign bodies in horses: 37 cases (1990-2005).

OBJECTIVE: To characterize features of diagnosis, treatment, and outcome in horses with foreign bodies, exclusive of enteric, inhaled, and foot-penetrating foreign bodies. DESIGN: Retrospective case series. ANIMALS: 37 horses with foreign bodies. PROCEDURES: The incidence of equine foreign bodies from 1990 through 2005 was determined by review of data from veterinary schools participating in the Veterinary Medical Database (VMDB). Medical records of horses with foreign bodies at Purdue University were reviewed, and the following information was retrieved: clinical history; signalment; results of physical, radiographic, and ultrasonographic examinations; results of microbial culture of the draining tract or foreign body material; surgical findings; antimicrobial and anti-inflammatory treatments; and complications of the surgical procedure. Long-term follow-up information was obtained from owners or referring veterinarians. RESULTS: The incidence of foreign bodies in horses with records in the VMDB was 1730/10,000 horse admissions. A preoperative diagnosis of foreign bodies was confirmed via ultrasonography in most horses examined (15/17 horses) and with plain film radiography in a quarter of horses examined (7/24 horses). Wood foreign bodies were the most common (59%; 22/37), followed by metal (24%; 9/37), hair (8%; 3/37), nonsequestrum bone (5%; 2/37), and plant material (3%; 1/37). Postoperative complications associated with the foreign body were more likely to develop with wood foreign bodies (3/22) than with other types of foreign bodies (1/15). CONCLUSIONS AND CLINICAL RELEVANCE: Wood was the most common penetrating foreign body in the horses in our study and was the type associated with the highest incidence of complications. Ultrasonography was more effective in locating foreign bodies than was radiography (plain and contrast) and should be performed in all horses with suspected foreign bodies.

Evaluation of the effects of transendoscopic diode laser palatoplasty on clinical, histologic, magnetic resonance imaging, and biomechanical findings in horses.

OBJECTIVE: To determine the effects of diode laser palatoplasty on the soft palate in horses. ANIMALS: 6 clinically normal horses and 6 euthanized horses from another study. PROCEDURES: 6 horses underwent diode laser palatoplasty (treated horses); 3 received low-dose laser treatment (1,209 to 1,224 J), and 3 received high-dose treatment (2,302 to 2,420 J). Six other horses received no treatment (control horses). The upper respiratory tracts of all treated horses were evaluated immediately following surgery (day 0) and on days 2, 7, 14, 21, 30, and 45. Horses were euthanized on day 45, and magnetic resonance imaging (MRI) of the head was performed. The soft palate was removed from treated and control horses, evaluated grossly, and scored for edema, inflammation, and scarring. Soft palates from all horses were sectioned for histologic and biomechanical evaluations. RESULTS: Endoscopic examination revealed a significant increase in soft palate scarring and decrease in edema and inflammation in treated horses by day 7. Gross postmortem findings corresponded with MRI findings. Gross and histologic examination revealed a significant increase in scarring, edema, and inflammation at day 45. Histologic evaluation of palatal tissue from high-dose-treated horses revealed full-thickness injury of skeletal muscle, with atrophy of muscle fibers; findings in low-dose-treated horses indicated superficial injury to skeletal muscle. After surgery, treated horses had a significant decrease in soft palate elastic modulus, compared with control horses. CONCLUSIONS AND CLINICAL RELEVANCE: Laser palatoplasty resulted in soft palate fibrosis and skeletal muscle loss; however, the fibrosis did not result in an increase in soft palate elastic modulus.

Treatment of acute epistaxis secondary to guttural pouch mycosis with transarterial nitinol vascular occlusion plugs in three equids.

CASE DESCRIPTION: 2 horses and 1 pony were evaluated for right-sided (1 horse and the pony) and left-sided (1 horse) acute epistaxis of 1 day's to 1 month's duration. CLINICAL FINDINGS: Endoscopic examination of the 3 equids revealed that the hemorrhage originated from the right maxillary artery in 2 equids and from the left internal carotid artery in the third. Mycosis of the auditory tube diverticulum (guttural pouch) was detected in all 3 equids. TREATMENT AND OUTCOME: All 3 equids underwent surgery, and transarterial nitinol intravascular plugs were placed to occlude affected blood vessels. All equids survived for a long period (ie, a minimum of 1 to 2 years) and returned to their previous use. All had complete regression of clinical signs of guttural pouch mycosis without additional medical treatment. CLINICAL RELEVANCE: The use of transarterial nitinol intravascular plugs appeared to be an effective alternative to other techniques for the treatment of epistaxis secondary to guttural pouch mycosis, including transarterial occlusion devices such as embolization coils.

Local neurotoxins for prevention of laryngeal synkinesis after recurrent laryngeal nerve injury.

OBJECTIVES: Persistent vocal fold motion impairment after recurrent laryngeal nerve (RLN) injury is not characteristically due to absent reinnervation, but often results from spontaneous aberrant reinnervation (synkinesis). We administered local neurotoxins to selected laryngeal muscles after RLN injury to determine whether aberrant reinnervation could be selectively inhibited. METHODS: Unilateral RLN transection was performed in 24 male rats. Three weeks later, the denervated laryngeal adductor complex was injected with phenol, high- or low-dose vincristine sulfate (VNC), or saline solution. One month later, rat larynges were evaluated via videolaryngoscopy and laryngeal electromyography (LEMG). Larynges from euthanized animals were analyzed via immunofluorescent staining for the presence of reinnervation. RESULTS: One animal that received phenol and 3 animals that received high-dose VNC died of toxicity-related complications. In the surviving neurotoxin-treated animals, videolaryngoscopy showed increased lateralization of the immobile vocal fold. Only 1 phenol-injected rat had adductor complex motor recruitment (score of 3+) with LEMG. The other neurotoxin-treated animals demonstrated an absence of adductor complex reinnervation, with only insertional activity and fibrillations (no motor units/recruitment). Spontaneous ipsilateral abductor reinnervation was not affected by the adductor injections. CONCLUSIONS: Low-dose VNC injections appear to be relatively safe and effective in selectively inhibiting spontaneous aberrant reinnervation after RLN injury in an animal model.

What is your diagnosis? Peritoneal fluid from an Arabian horse after colic surgery.

A 16-year-old castrated male Arabian horse was presented to the Purdue University Veterinary Teaching Hospital with a 4-hour history of colic. Initial examinations provided strong evidence for small intestinal obstruction. Abdominal surgery revealed a strangulating lipoma, and 25 feet of small intestine were resected. Postoperatively, the horse developed obstructive ileus due to adhesion formation, which required a second laparotomy. During and after surgery, the abdomen was lavaged with sodium carboxymethylcellulose (CMC). One week after the second surgery, evaluation of peritoneal fluid revealed an inflammatory exudate, with many macrophages containing amorphous to granular, pink to magenta phagocytosed material. Extracellular aggregates of the material were also observed. The material was consistent with CMC. To our knowledge, this report is the first to demonstrate the phagocytosis of CMC by peritoneal fluid macrophages.

Congenital retrosternal (Morgagni) diaphragmatic hernias in three horses.

CASE DESCRIPTION: 3 Horses were examined and treated because of sudden onset of signs of abdominal pain. CLINICAL FINDINGS: All horses had a retrosternal (Morgagni) hernia involving the right side of the diaphragm. In each horse, the large colon was incarcerated in a right muscular defect in the diaphragm with a large hernial sac. TREATMENT AND OUTCOME: Definitive surgical repair of the hernia was not performed during the initial celiotomy. The hernia was repaired with mesh herniorrhaphy, but without resection of the hernia sac in 2 horses. For 1 horse, conservative management was applied. In the 2 horses treated with surgical correction, no major postoperative complications developed, and all 3 horses have been free of signs of abdominal pain. CLINICAL RELEVANCE: Horses with retrosternal hernias involving the diaphragm can develop clinical signs of intermittent obstruction of the large colon and chronic colic. In horses, retrosternal diaphragmatic hernias appear to develop exclusively in the right ventral aspect of the diaphragm and could represent an embryologic defect of diaphragm formation. Affected horses can be successfully treated with mesh herniorrhaphy or, in some instances, with conservative management.

Evaluation of transfixation casting for treatment of third metacarpal, third metatarsal, and phalangeal fractures in horses: 37 cases (1994-2004).

OBJECTIVE: To evaluate clinical findings, complications, and outcome of horses and foals with third metacarpal, third metatarsal, or phalangeal fractures that were treated with transfixation casting. DESIGN: Retrospective case series. Animals-29 adult horses and 8 foals with fractures of the third metacarpal or metatarsal bone or the proximal or middle phalanx. PROCEDURES: Medical records were reviewed, and follow-up information was obtained. Data were analyzed by use of logistic regression models for survival, fracture healing, return to intended use, pin loosening, pin hole lysis, and complications associated with pins. RESULTS: In 27 of 35 (77%) horses, the fracture healed and the horse survived, including 10 of 15 third metacarpal or metatarsal bone fractures, 11 of 12 proximal phalanx fractures, and 6 of 8 middle phalanx fractures. Four adult horses sustained a fracture through a pin hole. One horse sustained a pathologic unicortical fracture secondary to a pin hole infec-tion. Increasing body weight, fracture involving 2 joints, nondiaphyseal fracture location, and increasing duration until radiographic union were associated with horses not returning to their intended use. After adjusting for body weight, pin loosening was associated with di-aphyseal pin location, pin hole lysis was associated with number of days with a transfixation cast, and pin complications were associated with hand insertion of pins. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that transfixation casting can be successful in managing fractures distal to the carpus or tarsus in horses. This technique is most suitable for comminuted fractures of the proximal phalanx but can be used for third metacarpal, third metatarsal, or middle phalanx fractures, with or without internal fixation.

Evaluation of surgical treatment for signs of acute abdominal pain in draft horses: 72 cases (1983-2002).

OBJECTIVE: To determine whether heavy (> or = 680 kg [> or = 1,500 lb]) draft horses undergoing surgical treatment for acute signs of abdominal pain were at a greater risk for anesthetic and postoperative complications and lower postoperative survival rates than light (< 680 kg) draft horses. DESIGN: Retrospective case series. ANIMALS: 72 draft horses. PROCEDURES: Medical records of draft horses that underwent exploratory celiotomy for signs of acute abdominal pain from October 1983 to December 2002 were reviewed. Medical records of draft horses in which a celiotomy was performed for correction of reproductive abnormalities were not included in the study. RESULTS: When compared with light draft horses, heavy draft horses had longer durations of anesthesia, more postoperative complications, and lower survival rates. Seventy-six percent of horses that recovered from anesthesia had postoperative complications. Postoperative complications associated with low survival rates included myopathy and neuropathy, ileus, diarrhea, and endotoxemia. All horses with postoperative myopathy and neuropathy died or were euthanized. The short-term survival rate for horses that recovered from anesthesia was 60%. Horses undergoing small intestinal surgery had a worse prognosis for short-term survival than those undergoing large intestinal surgery. The survival rate for horses for which long-term (> 1 year) follow-up information was available was 50%. CONCLUSIONS AND CLINICAL RELEVANCE: Draft horses weighing > 680 kg that underwent surgery because of acute signs of abdominal pain had longer durations of anesthesia, more postoperative complications, and higher mortality rates than draft horses weighing < 680 kg.

Retinoblastoma in the eye of a llama (Llama glama).

ANIMAL STUDIED: A 6-year-old, pregnant female llama experienced a 6-month history of epiphora, buphthalmos, and acute loss of vision in the left eye. The condition was unresponsive to topical antimicrobial and anti-inflammatory therapy and progressed to corneal rupture. PROCEDURES: Transpalpebral enucleation was performed and an intraorbital silicone prosthesis was implanted. The eye was fixed in formalin and processed according to routine paraffin technique. Sections of a mass were immunohistochemically prepared routinely and stained for glial fibrillary acidic protein (GFAP), S-antigen, and rhodopsin. RESULTS: Gross, histopathologic, and immunohistochemical analysis revealed a retinal tumor consistent with a retinoblastoma. The neoplastic tissue formed Flexner-Wintersteiner and Homer-Wright rosettes, originated from the retina, and demonstrated photoreceptor differentiation with S-antigen and rhodopsin expression. Neoplastic cells were negative for GFAP. Four years after enucleation, the llama showed no signs of recurrent neoplasia. CONCLUSIONS: This report describes the diagnosis and successful treatment of the first known retinoblastoma in a llama.