Open drainage, intra-articular and systemic antibiotics in the treatment of septic arthritis/tenosynovitis in horses.

Open drainage was used to treat 26 horses with persistent or severe septic arthritis/tenosynovitis. Infected synovial structures were drained through a small (3 cm) arthrotomy incision that was left open and protected by a sterile bandage. Joint lavage was performed in all 26 horses. In addition to systemic antibiotics, 23 of these horses were also treated with intra-articular antibiotics; amikacin (17 horses), gentamycin (2 horses), cefazolin (2 horses), and 2 horses were injected at different times with gentamycin and amikacin. The infection was eliminated from the involved synovial structures in 25 of 26 horses; 24 survived and were released from the hospital. The arthrotomy incisions healed by granulation in 16 horses; in 9 horses the arthrotomy incision was sutured closed once the infection was eliminated. Seventeen horses returned to soundness and resumed athletic function. Open drainage was an effective method of achieving chronic drainage from a joint or tendon sheath. It is indicated in horses that have established intra-synovial infections or in horses that do not respond to joint lavage through needles.     

Treatment of traumatic arthritis in the horse with intra-articular orgotein (palosein)

A total of 134 horses of various breeds were treated for aseptic arthritis of traumatic origin using Orgotein (Palosein). The drug was injected into 192 affected joints of these animals. Recovery rates of 94 per cent were recorded in cases which had shown lameness for less than 2 months before treatment commenced and 49 per cent in those lame for longer than 2 months.     

Use of infrared spectroscopy for diagnosis of traumatic arthritis in horses

OBJECTIVE: To evaluate use of infrared spectroscopy for diagnosis of traumatic arthritis in horses. ANIMALS: 48 horses with traumatic arthritis and 5 clinically and radiographically normal horses. PROCEDURES: Synovial fluid samples were collected from 77 joints in 48 horses with traumatic arthritis. Paired samples (affected and control joints) from 29 horses and independent samples from an affected (n = 12) or control (7) joint from 19 horses were collected for model calibration. A second set of 20 normal validation samples was collected from 5 clinically and radiographically normal horses. Fourier transform infrared spectra of synovial fluids were acquired and manipulated, and data from affected joints were compared with controls to identify spectroscopic features that differed significantly between groups. A classification model that used linear discriminant analysis was developed. Performance of the model was determined by use of the 2 validation datasets. RESULTS: A classification model based on 3 infrared regions classified spectra from the calibration dataset with overall accuracy of 97% (sensitivity, 93%; specificity, 100%). The model, with cost-adjusted prior probabilities of 0.60:0.40, yielded overall accuracy of 89% (sensitivity, 83%; specificity, 100%) for the first validation sample dataset and 100% correct classification of the second set of independent normal control joints. CONCLUSIONS AND CLINICAL RELEVANCE: The infrared spectroscopic patterns of fluid from joints with traumatic arthritis differed significantly from the corresponding patterns for controls. These alterations in absorption patterns may be used via an appropriate classification algorithm to differentiate the spectra of affected joints from those of controls.     

Hyaluronic acid in synovial fluid. VI. Effect of intra-articular injection of hyaluronic acid on the clinical symptoms of arthritis in track horses

Twelve horses with traumatic arthritis were treated with intraarticular injection of hyaluronic acid mixed with cortisone and the results compared with 6 horses treated only with cortisone. There was a significantly better improvement in the group injected with a mixture of hyaluronic acid and cortisone. Further studies have given the same results in traumatic arthritis in horses if hyaluronic acid alone is injected.After injection of hyaluronic acid a large number of granulated monocytes appeared in the synovial fluid, but no inflammatory signs were observed. It is possible that this macrophage invasion is instrumental in producing improvement in the condition of the joint. The injected hyaluronic acid may also adhere to the surface of articular cartilage producing an “clastic cushion” protecting the cartilage surface.Experimental mechanical damage was also inflicted on the surface of articular cartilage in dogs and monkeys, and smoother healing was achieved if hyaluronic acid was injected into the joints after the damage.Injections of hyaluronic acid seem to be of value in treating traumatic arthritis or similar conditions.     

Comparison of intra-articular drilling and diode laser treatment for arthrodesis of the distal tarsal joints in normal horses

REASONS FOR PERFORMING STUDY: Anecdotal reports suggest that laser-facilitated arthrodesis of the distal tarsal joints improves the prognosis compared with intra-articular drilling but no objective comparisons have been performed. OBJECTIVES: To evaluate intra-articular drilling and laser-facilitated arthrodesis using in situ and in vivo techniques. METHODS: Fourteen cadaver limbs were evaluated in situ for chondrocyte viability after both surgical techniques. In vivo, one randomly selected limb was subjected to laser-facilitated arthrodesis and the other underwent intra-articular drilling in 6 normal horses. Clinical examinations were performed at 1, 3 and 5 months. Two horses were subjected to euthanasia at 1, 3 and 5 months. RESULTS: Significantly more chondrocyte death was observed with laser-facilitated arthrodesis compared to drilling, but the overall degree suggested only a focal effect. In vivo, both groups demonstrated minimal post operative morbidity. There was more evidence of arthrodesis seen at all time points with intra-articular drilling. CONCLUSIONS: This study demonstrated that changes associated with ultimate arthrodesis occur earlier after intra-articular drilling of the distal tarsal joints than laser-facilitated arthrodesis, although clinically affected horses may respond differently. POTENTIAL RELEVANCE: Intra-articular drilling may provide earlier arthrodesis of the distal tarsal joints, but not necessarily a better long-term result.     

Epidural migration of new methylene blue in 0.9% sodium chloride solution or 2% mepivacaine solution following injection into the first intercoccygeal space in foal cadavers and anesthetized foals undergoing laparoscopy

OBJECTIVE: To determine the relationship between epidural cranial migration and injectate volume of an isotonic solution containing dye in laterally recumbent foal cadavers and evaluate the cranial migration and dermatome analgesia of an epidural dye solution during conditions of laparoscopy in foals. ANIMALS: 19 foal cadavers and 8 pony foals. PROCEDURES: Foal cadavers received an epidural injection of dye solution (0.05, 0.1, 0.15, or 0.2 mL/kg) containing 1.2 mg of new methylene blue (NMB)/mL of saline (0.9% NaCl) solution. Length of the dye column and number of intervertebral spaces cranial and caudal to the injection site were measured. Anesthetized foals received an epidural injection of dye solution (0.2 mL/kg) containing saline solution or 2% mepivacaine. Foals were placed in a 100 head-down position, and pneumoperitoneum was induced. Dermatome analgesia was determined by use of a described electrical stimulus technique. Foals were euthanatized, and length of the dye column was measured. RESULTS: Epidural cranial migration of dye solution in foal cadavers increased with increasing volume injected. No significant difference was found in epidural cranial migration of a dye solution (0.2 mL/kg) between anesthetized foals undergoing conditions of laparoscopy and foal cadavers in lateral recumbency. Further craniad migration of the dye column occurred than indicated by dermatome analgesia. CONCLUSIONS AND CLINICAL RELEVANCE: Epidural cranial migration increases with volume of injectate. On the basis of dermatome analgesia, an epidural injection of 2% mepivacaine (0.2 mL/kg) alone provides analgesia up to at least the caudal thoracic dermatome and could permit caudal laparoscopic surgical procedures in foals.     

Conservative treatment of intra-articular distal phalanx fractures in horses not used for racing

OBJECTIVE: To determine the success rate and whether specific patient and treatment factors influenced the outcome after conservative treatment with a bar shoe with quarter clips of intra-articular fractures of the distal phalanx in horses not used for racing. DESIGN: Retrospective study. SAMPLE POPULATION: Thirty-two client-owned horses. PROCEDURE: Hospital records of horses that had been treated conservatively for intra-articular fractures of the distal phalanx at Skara Equine Hospital or Halland Animal Hospital in Sweden between 1995 and 2001 were reviewed. Racehorses in active training and horses affected with other musculoskeletal diseases were excluded from the study. Follow-up was performed by questionnaire and telephone inquires to the owners 1 to 7 years after injury. RESULTS: Twenty-two horses (69%) returned to their previous or expected level of use and did not wear their bar shoe when they were put back into training. There was no statistically significant correlation between outcome and patient or treatment variables, or bony union of the fracture. CONCLUSIONS AND CLINICAL RELEVANCE: Conservative treatment of intra-articular fractures of the distal phalanx carries a fair prognosis for return to previous or expected level of use in horses not used for racing. Radiographic evidence of fracture healing and age of the patient do not seem to influence the prognosis. Horses not used for racing do not need to be shod with a bar shoe with quarter clips for the rest of their athletic career.     

Comparison of high-performance liquid chromatography with a radiometric assay for determination of the effect of intra-articular administration of corticosteroid and saline solution on synovial fluid hyaluronate concentration in horses.

Two recently developed direct methods, radioassay-125I-labeled hyaluronic acid binding protein (125I-HABP)- and high-performance liquid chromatography (HPLC), were used to assess and compare the concentration of hyaluronate (HA) in synovial fluid of horses. Also determined were changes in the HA concentration in an experimental treatment model involving physiologic saline solution (PSS)-irrigated or methylprednisolone acetate-injected tarsocrural joints of clinically normal horses. Serum HA concentration was determined simultaneously, using the 125I-HABP assay. Synovial fluid HA concentration values obtained by use of the HPLC method were approximately double the values obtained by use of 125I-HABP assay. Correlation (r = 0.819) between the 2 methods was highly significant (P less than 0.001; linear regression analysis) for all samples studied and for various experimental subgroups. When pure HA standards were used, correlation between the 2 methods was close to 1 (r = 0.965; P less than 0.001), with higher values obtained by use of the 125I-HABP assay. It is suggested that the HA binding protein derived from endogenous cartilage proteoglycan interferes with the 125I-HABP assay on synovial fluid, resulting in excessively low values, compared with those obtained using the HPLC procedure. Intra-articular injection of methylprednisolone acetate significantly (P less than 0.01) increased synovial fluid HA concentration at 24 hours after injection. Increase was also detected after PSS irrigation, but owing to wide intersubject variation, this increase was not significant. The HPLC procedure, which provides simultaneous information about the concentration and degree of polymerization of HA, is recommended for the study of synovial fluid, whereas the 125I-HABP assay is more suitable for serum HA analysis.     

Alternative antiparasitic treatment of horses with pyrantel pamoate suspension and ivermectin oral solution compared with horses treated only with ivermectin oral solution

A practical parasite control program was evaluated in a 2-year clinical trial using pyrantel pamoate suspension (PYR) and ivermectin oral solution (IVM) in a seasonal rotation program, in comparison with continued use of IVM given at 2-month intervals. At least 15 horses in each of 2 treatment groups were distributed over 8 locations. In the alternation program, IVM was given twice (October, December) during the botfly (Gasterophilus spp.) season and again in April to treat against the lighter botfly season and to kill existing Onchocerca microfilariae prior to heavy Culicoides swarming. Pyrantel was given in February, June and August to continue suppression of strongyle infections and to treat against potentially developing Anoplocephala infections. In the program of IVM continuous use, the drug was given on the same schedule as either treatment on the alternation program.The course of strongyle infections was monitored by fecal sample analyses (EPG) at semimonthly intervals and by larval cultures of treatment pairs prepared at each treatment interval (alternation program) or at 4-month intervals (continuous IVM program). The strongyle egg count numbers were reduced to zero by the first IVM treatment, increased only slightly by the next treatment at 2 months, and repeated the reduced pattern with each treatment for 2 years. The alternation program in the first year had typical responses to each drug: IVM reducing strongyle EPG counts to zero which increased slightly at 2 months, followed by the PYR treatment, which reduced the strongyle egg counts for 4 weeks with rebound at 6 and 8 weeks. At the end of the first year and into the second, the IVM treatments of October and December established a zero or low strongyle EPG pattern which continued through the spring with PYR and IVM treatments. The second summer PYR treatments then maintained far better cyathostome control than had been reported for this drug. There may be a complementary or enhancing effect by prior treatment with ivermectin within the rotation protocol. The practical therapeutic compatibility between these 2 antiparasitics became obvious. Anoplocephala eggs were found in feces of some horses treated with IVM only, but no Anoplocephala eggs were found in post-treatment feces of horses treated on the alternation program.Strongyle larval cultures prepared as treatment pairs indicated high efficacy by ivermectin throughout the 2 years whether used alone or as a rotational drug, with improved cyathostome control by pyrantel pamoate. The combined use of EPG determinations and concurrent larval cultures in anthelmintic evaluations provide a greater spectrum of reliable results than from parasite egg counts alone.     

Comparison of two techniques for injection of the podotrochlear bursa in horses

OBJECTIVE: To compare accuracy of 2 methods for injection of the podotrochlear bursa in horses. DESIGN: Observational study. ANIMALS: 17 French Standardbreds. PROCEDURE: In each horse, contrast medium was injected into the podotrochlear bursa of 1 foot by use of a distal palmar approach with the needle inserted parallel to the sole (DPPS) and into the podotrochlear bursa of the other foot by use of a distal palmar approach to the navicular position (DPNP). Podotrochlear bursa injection was evaluated by means of radiographic examination in all horses and postmortem examination in 6. RESULTS: Contrast medium was successfully injected into the podotrochlear bursa in 6 of 16 feet in which the DPPS method was used and 14 of 17 feet in which the DPNP method was used; these results were significantly different. Failure was attributed to contrast medium invading the distal interphalangeal joint, contrast medium pooling palmar to the deep digital flexor tendon, contrast medium located in the podotrochlear bursa and the distal interphalangeal joint, contrast medium located in the podotrochlear bursa and the area palmar to the deep digital flexor tendon, and an inability to inject contrast medium despite adequate needle placement. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the DPNP technique can be used successfully for injection into the podotrochlear bursa in horses. However, radiographic assessment should be used to confirm that material was injected into the bursa.     

Effects of topical administration of 0.005% latanoprost solution on eyes of clinically normal horses.

OBJECTIVE: To determine the effect of 0.005% latanoprost solution on intraocular pressure (IOP) of eyes of clinically normal horses and establish the frequency of adverse effects of drug administration. ANIMALS: 20 adult clinically normal horses. PROCEDURE: IOP was recorded (7, 9, and 11 AM; 3, 5, and 7 PM) on days 1 and 2 (baseline), days 3 to 7 (treatment), and days 8 to 9 (follow-up). Latanoprost was administered to 1 randomly assigned eye of each horse every 24 hours during the treatment period, following the 7 AM IOP recording. Pupil size and the presence or absence of conjunctival hyperemia, epiphora, blepharospasm, blepharedema, and aqueous flare were recorded prior to IOP measurement. RESULTS: IOP was reduced from baseline by a mean value of 1.03 mm Hg (5%) in males and 3.01 mm Hg (17%) in females during the treatment period. Miosis developed in all treated eyes and was moderate to marked in 77% of horses, with the peak effect observed 4 to 8 hours after drug administration. Conjunctival hyperemia, epiphora, blepharospasm, and blepharedema were present in 100, 57, 42, and 12% of treated eyes, respectively, 2 to 24 hours following drug administration. Aqueous flare was not observed at any time point. CONCLUSIONS AND CLINICAL RELEVANCE: Although IOP was reduced with every 24-hour dosing of latanoprost, the frequency of prostaglandin-induced adverse events was high. Because recurrent uveitis appears to be a risk factor for glaucoma in horses, topical administration of latanoprost may potentiate prostaglandin-mediated inflammatory disease in affected horses.     

Results of renal ultrasonography performed before and during administration of saline (0.9% NaCl) solution to induce diuresis in dogs without evidence of renal disease

OBJECTIVE: To evaluate the effect of saline (0.9% NaCl) solution administered IV to induce diuresis on 15 dimensional variables of the kidneys, size of renal pelvis, and diameter of the cranial part of the ureters. ANIMALS: 25 dogs without evidence of renal disease that were undergoing chemotherapy for various neoplasms. PROCEDURE: The kidneys, cranial aspect of the ureters, and trigone area of the urinary bladder of each dog were examined ultrasonographically before and during IV administration of saline solution (2.7 to 18.8 ml/kg of body weight/h). RESULTS: Ultrasonography revealed unilateral and bilateral pyelectasis during diuresis in 16 of 23 (70%) dogs but unilateral pyelectasis in only 1 dog before diuresis. Unilateral pyelectasis during diuresis was observed in 11 of 16 (69%) dogs. Pyelectasis during diuresis was categorized as slight in 15 of 21 (71%) kidneys. Degree of pyelectasis during diuresis was not identical in both kidneys of 13 of 16 (81 %) dogs. Diuresis did not induce ureterectasis, and it did not cause changes in 15 dimensional variables of the kidneys. CONCLUSIONS: In nonsedated, nonazotemic dogs, IV administration of saline solution to induce diuresis may cause slight pyelectasis without evidence of ureterectasis. CLINICAL RELEVANCE: When dilatation of the cranial part of the ureter is > 2 mm at the same time that ipsilateral pyelectasis is detected during ultrasonographic examination of the urinary tract system of a nonsedated, nonazotemic dog receiving IV administration of saline solution to induce diuresis, additional examinations are recommended to determine the possibility of early obstructive nephropathy or pyelonephritis.     

Evaluation of intra-articular injection of autologous platelet lysate (PL) in horses with osteoarthritis of the distal interphalangeal joint

Background: Regenerative medicine has become one of the most promising therapies of equine osteoarthritis. Platelet lysate (PL) is rich in bioactive proteins and growth factors that play a crucial role in tissue healing.

Objective: To evaluate the efficacy of intra-articularly injected autologous PL in equine athletes with naturally occurring osteoarthritis.

Animals and methods: Fifteen warmblood geldings aged 8–19 years with osteoarthritis of the distal interphalangeal joint were included in this study. They were randomly divided into two groups; 10 horses received intra-articular injections of PL and 5 of normal saline (controls). Before treatment, platelet-derived growth factor (PDGF) levels in basal plasma and prepared PL were estimated. Each joint was injected twice within a three-week period. Lameness was evaluated using the American Association of Equine Practitioners grading system, before treatment and 10 days after each intra-articular injection. Horses were examined fortnightly for one year. Radiographic examination was performed six months post-treatment. The generalized estimating equation test was used for statistical analysis.

Results: Acceptable levels of PDGF were detected in PLs (mean ± SD: 258.0 ± 52.3 pg/ml). The majority of horses (9/10) responded positively to PL treatment presenting lower lameness grades (p < 0.0005) compared to controls 10 days after the second injection, and returned to normal athletic activity. Radiographs revealed no changes in osteoarthritis lesions six months after treatment. One year post-injections, however, all horses relapsed to their initial degree of lameness.

Conclusion: Intra-articularly injected autologous PL is an efficient method for temporarily managing osteoarthritis of the distal interphalangeal joint in athletic horses.     

Arthrotomy versus arthroscopy and partial synovectomy for treatment of experimentally induced infectious arthritis in horses.

To evaluate the clinical, laboratory, and histologic effects of 2 methods of treatment for infectious arthritis in horses, Staphylococcus aureus (3.4 to 3.9 x 10(3) colony-forming units) was inoculated into the tarsocrural joints of 8 horses on day 0. Each horse was treated with phenylbutazone (2 g, PO, q 24 h) and gentamicin sulfate (2.2 mg/kg of body weight, IV, q 8 h) for 14 days. On day 2, general anesthesia was induced, and each horse had 1 tarsocrural joint treated by arthrotomy, with removal of accessible fibrin and lavage with 3 L of sterile balanced electrolyte solution. An indwelling plastic drain was placed in the standing horse to provide a means for lavage with 3 L of balanced electrolyte solution twice daily for 72 hours. The contralateral tarsocrural joint was treated via arthroscopic debridement, synovectomy, and lavage with 3 L of balanced electrolyte solution. Arthrotomy and arthroscopic portals were allowed to heal by second intention. Lameness and thermographic examinations, analysis and bacteriologic culture of synovia, CBC, and WBC differential count were performed prior to inoculation and on days 1, 3, 6, 8, and 13. On day 14, each horse was euthanatized, and the joints were measured, opened, and photographed. Synovium and articular cartilage were obtained for semiquantitative histologic (H&E stain) and histochemical (safranin O fast green stain) evaluation. Lameness and joint circumference were significantly (P less than 0.05) greater in limbs treated by arthroscopy, synovectomy, and lavage. Arthrotomy with lavage eliminated the S aureus infection significantly (P less than 0.05) earlier than arthroscopy, synovectomy, and lavage, however, both treatments eliminated the infection in all but a single joint.(ABSTRACT TRUNCATED AT 250 WORDS)     

Alternative antiparasitic treatment of horses with pyrantel pamoate suspension and ivermectin oral solution compared with horses treated only with ivermectin

A practical parasite control program was evaluated in a 2-year clinical trial using pyrantel pamoate suspension (PYR) and ivermectin oral solution (IVM) in a seasonal rotation program, in comparison with continued use of IVM given at 2-month intervals. At least 15 horses in each of 2 treatment groups were distributed over 8 locations. In the alternation program, IVM was given twice (October, December) during the botfly (Gasterophilus spp.) season and again in April to treat against the lighter botfly season and to kill existing Onchocerca microfilariae prior to heavy Culicoides swarming. Pyrantel was given in February, June and August to continue suppression of strongyle infections and to treat against potentially developing Anoplocephala infections. In the program of IVM continuous use, the drug was given on the same schedule as either treatment on the alternation program.The course of strongyle infections was monitored by fecal sample analyses (EPG) at semimonthly intervals and by larval cultures of treatment pairs prepared at each treatment interval (alternation program) or at 4-month intervals (continuous IVM program). The strongyle egg count numbers were reduced to zero by the first IVM treatment, increased only slightly by the next treatment at 2 months, and repeated the reduced pattern with each treatment for 2 years. The alternation program in the first year had typical responses to each drug: IVM reducing strongyle EPG counts to zero which increased slightly at 2 months, followed by the PYR treatment, which reduced the strongyle egg counts for 4 weeks with rebound at 6 and 8 weeks. At the end of the first year and into the second, the IVM treatments of October and December established a zero or low strongyle EPG pattern which continued through the spring with PYR and IVM treatments. The second summer PYR treatments then maintained far better cyathostome control than had been reported for this drug. There may be a complementary or enhancing effect by prior treatment with ivermectin within the rotation protocol. The practical therapeutic compatibility between these 2 antiparasitics became obvious. Anoplocephala eggs were found in feces of some horses treated with IVM only, but no Anoplocephala eggs were found in post-treatment feces of horses treated on the alternation program.Strongyle larval cultures prepared as treatment pairs indicated high efficacy by ivermectin throughout the 2 years whether used alone or as a rotational drug, with improved cyathostome control by pyrantel pamoate. The combined use of EPG determinations and concurrent larval cultures in anthelmintic evaluations provide a greater spectrum of reliable results than from parasite egg counts alone.