Pancarpal Arthrodesis for Treatment of Carpal Collapse in the Adult Horse A Report of Two Cases

Two mares with multiple carpal bone fractures, malarticulation and degenerative joint disease were successfully treated with unilateral arthrodeses of the antebrachiocarpal, middle carpal, and carpometacarpal joints. Arthrodesis was achieved by removal of articular cartilage, autogenous cancellous bone graft, and double dynamic compression plating. In one horse, wedge ostectomy corrected the severe, acquired angular limb deformity. External coaptation supplemented the internal fixation. Postoperative complications were limited to cast sores that healed with treatment, although protracted in one horse. Both mares adapted to the "peg leg" condition and ambulated without pain by 3 months. The first mare treated survived for at least 2 1/2 years after surgery and has had at least one foal. The most recently treated mare will be bred next year.     

Pancarpal Arthrodesis in the Dog: A Review of Forty-five Cases

This report describes an open surgical technique for pancarpal arthrodesis and its efficacy in 45 canine cases. Indications for carpal arthrodesis include hyperextension injuries, severe fracture/luxations, end-stage arthritis, and selected neurologic deficits. Chronic joint instability was the major indication for surgery (76%). Degenerative joint disease (18%) and neurologic deficits (6%) accounted for the other cases. In a subjective owner survey, 97% of the owners reported that their animals' gait improved following arthrodesis, and 74% stated that their animals walked and ran normally.     

Carpal Joint Arthrodesis as a Treatment for Chronic Septic Carpitis in Calves and Cattle

Chronic septic carpitis in 72 calves and adult cattle was treated by arthrodesis of the carpus (n = 24), proximal or distal carpal row resection with arthrodesis (n = 31), or resection of both the proximal and distal carpal bones and radio-metacarpal arthrodesis (n = 17). Painfree arthrodesis permitting full weight-bearing was obtained in 69% of the cases. Arthrodesis without resection of carpal bones was successful in 87% of the cases. With resection of one carpal row, 72% of the cases were treated successfully. Radio-metacarpal arthrodesis with removal of both carpal rows resulted in fusion in 35% of the animals.     

Lag Screw Fixation of a Sagittal Fracture of the Third Carpal Bone in a Horse

A sagittal fracture of the third carpal bone of a Standardbred racehorse was repaired with lag screw fixation. Healing of the fracture was uncomplicated, and the horse made a successful return to racing. It was concluded that selected sagittal fractures of the third carpal bone may be treated successfully with lag screw fixation. Criteria for selection of cases include fragment size and orientation of the fracture plane.     

A Prosthetic Implant for the Equine Carpal Joint: Surgical Technique and Results

A prosthesis designed to partially replace the articular surfaces of the radial and third carpal bones was implanted bilaterally in 6 normal horses. The prosthesis consisted of a convex metal alloy component, and a concave ultra-high molecular weight polyethylene component, for implantation into the radial and third carpal bones, respectively. One horse underwent the soft tissue approach only to serve as a control. Effects on joint motion and pathologic changes were monitored over a 6-month period using clinical examination, synovial fluid analysis, electrogoniometry, high-speed cinematography, radiography, and gross and microscopic pathologic examination. Six months following implantation, all horses that received implants would trot, with slight to moderate lameness. Electrogoniometric and cinematographic evaluation of joint motion demonstrated a reduction in amplitude of the carpus in 4 horses receiving implants; however, in 2 horses, the reduction was less than, or equivalent to, that of the control horse. One horse that received the prosthesis was rideable, and was able to run with minimal lameness. Radiography, synovial fluid analysis, and gross and microscopic pathologic examination revealed varying degrees of synovitis and osteoarthritis. Biomechanical alterations of the middle carpal joint and release of wear particles from the prosthesis were considered to be major causes of these secondary changes. Changes in design of the prosthesis, intended to more accurately maintain normal joint biomechanics are proposed.     

Synovial Fluid and Clinical Changes After Arthroscopic Partial Synovectomy of the Equine Middle Carpal Joint

Changes in synovial fluid and clinical variables after arthroscopic partial synovectomy of the middle carpal joint were studied in 12 normal horses. A 7 mm motorized synovial resector was inserted into each middle carpal joint; one middle carpal joint of each horse was randomly selected to have arthroscopic synovectomy (treated) and the opposite joint was lavaged (control). Lameness examinations and synovial fluid analyses were performed before operation and at 8, 14, 21, and 28 days after operation. Lameness variables did not differ between treated and control legs. Middle carpal and carpometacarpal joint circumference measurements were increased for 4 weeks. Synovial fluid specific gravity, pH, total protein, albumin concentration, and alpha-1-, beta- and gamma-globulin concentrations, at 8 and 14 days were significantly higher than before operation in both treated and control middle carpal joints. No significant differences were found between treated and control middle carpal joints at any time for color, clarity, pH, mucin clot formation, total protein, albumin, and globulin fractions. Arthroscopic partial synovectomy and lavage did not cause significant lameness and resulted in a synovitis indistinguishable from synovitis related to arthroscopic lavage alone.     

Arthrodesis of the shoulder for synovial osteochondromatosis

A case of synovial osteochondromatosis (SOC) in a young deerhound's shoulder is reviewed. The age of onset and initially unaffected articular surfaces suggested primary SOC. Histological criteria for primary versus secondary osteochondromatosis are contradictory and unclear. Initial loose body removal and partial synovectomy resulted in several months of Improvement but loose bodies returned. Severe degenerative changes were found one year after the initial exploratory surgery. Arthrodesis resulted in a functional, non-painful joint.     

Biomechanical Comparison of the Herbert and AO Cortical Bone Screws for Compression of an Equine Third Carpal Bone Dorsal Plane Slab Osteotomy

Objective—To assess feasibility of insertion of 4.5-mm Herbert cannulated bone screws (HS) using fluoroscopic guidance and compare the mechanical shear strength of these HS and 4.5-mm AO cortical bone screws (AO) for fixation of dorsal plane slab osteotomies in equine cadaver third carpal bones (C3).
Animals or Sample Population—Eight equine cadavers.
Methods—Bone mineral composition and density of contralateral C3 were confirmed to be equivalent using dual-energy x-ray absorptiometry. A standard 10-mm C3 slab osteotomy was reduced using HS or AO instrumentation under fluoroscopic guidance. Specimens were loaded in shear until failure, using a materials testing apparatus.
Results—HS and AO instrumentation allowed accurate reconstruction of the osteotomy, but there was difficulty encountered seating the HS proximal self-tapping threads. There was no significant difference in maximal load to failure, stiffness, or mode of failure of constructs created with the HS and AO screws.
Conclusions —Use of 4.5-mm HS for repair of C3 radial facet, dorsal plane slab fractures may result in a mechanically comparable fixation to a repair using a 4.5-mm AO. Equine dorsal C3 may be too dense, however, to allow placement of the proximal self-tapping threads of the HS without potentially excessive application of torque to the screw itself.
Clinical Relevance —Dorsal plane, radial facet slab fractures of the equine C3 are a significant clinical problem. Accurate reconstruction and stabilization are necessary for return to athletic function.     

Complications and Long-term Results after Partial Laryngectomy for the Treatment of Idiopathic Laryngeal Paralysis in 45 Dogs

Forty-five dogs with severe respiratory signs caused by idiopathic, acquired laryngeal paralysis were treated by partial laryngectomy. The predominant postoperative complications were coughing in 28 dogs and pneumonia in 15 dogs. Eight dogs required a second operation to alleviate persistent or recurrent upper airway obstruction. Results of surgery were considered excellent in 11 dogs (25%), good in 18 dogs (40%), fair in 6 dogs (13%), and poor in 10 dogs (22%). Poorer results were obtained by surgical residents than by more experienced surgeons. Death in the immediate postoperative period was related to pneumonia (8 dogs) and laryngeal collapse (1 dog). Nine dogs died later of respiratory disease. Although partial laryngectomy is effective for the treatment of laryngeal paralysis, it is not recommended because of the high incidence of postoperative complications.     

A Modified Cloward''s Technique for Arthrodesis of the Normal Metacarpophalangeal Joint in the Horse

A modified Cloward's technique was performed for arthrodesis of one metacarpophalangeal (MCP) joint in eight horses. Dorsal arthrotomies were performed medial and lateral to the common digital extensor tendon and two 16 mm holes were drilled through the joint. A perforated cylindrical stainless steel basket filled with cancellous bone was impacted into each hole. The limbs were supported in casts for 8 weeks. The joints were examined and radiographed at 4 weeks, 8 weeks, 6 months, and 10 months. One horse was euthanatized at week 14 to assess the progress of the arthrodesis. In the other seven horses, there was clinical fusion at month 6. Dynamographic evaluations were performed 11 months after surgery at the walk and trot. The maximum vertical forces exerted during weight bearing by treated and control limbs were compared. No difference was detected at the walk; however, a significant difference was present at the trot (p less than 0.05). It was calculated that at the trot the horses placed 90% as much force on the treated limb as on the control limb. Eleven months after surgery, the baskets contained compact and cancellous bone. Ingrowth of bone occurred through all openings, completely filling the baskets and fusing the joints.     

Arthrodesis for congenital luxation of the shoulder in a dog

Congenital luxation of the shoulder in a 7-month-old Chihuahua was corrected by use of arthrodesis. A single lag-screw fixation technique was used. Arthrodesis of the shoulder provides a favorable alternative to other salvage techniques such as glenohumeral resection or amputation.     

Electrosurgery: A Review

This article presents a review of hemostasis and electrosurgery. The principles of electrosurgery, including the effect on tissue, vessels, and wound healing, are presented, as are the advantages and disadvantages of its use.     

Arthrodesis for Congenital Flexural Deformity of the Metacarpophalangeal and Metatarsophalangeal Joints

A llama, a miniature horse, and a miniature donkey with severe bilateral congenital flexural deformities of the metacarpophalangeal and metatarsophalangeal joints were treated successfully by arthrodesis with dynamic compression plating or external skeletal fixation. The flexor tendons were more taut than the suspensory ligaments and were transected. In the llama, the suspensory ligament was transected, and overcorrection caused ischemic necrosis of one distal limb and subluxation of the other fetlock joint. In the horse and donkey, the suspensory ligament was preserved and wedge osteotomy was performed to correct the deformity.     

Comparison of Three Drilling Techniques for Carpometacarpal Joint Arthrodesis in Horses

Objective: To evaluate 3 drilling techniques for arthrodesis of the equine carpometacarpal (CMC) joint. Study Design: Experimental study. Sample Population: Cadaveric equine forelimbs (n=15). Methods: Limbs were divided into 3 groups (5 limbs each) to evaluate 3 drilling techniques: (1) use of a 4.5 mm drill bit inserted into the joint through 4 entry points and moved in a fanning motion; (2) a 5.5 mm drill bit inserted through 2 entry points to create 3 nonfanned drill tracts (3 drill technique); and (3) a 4.5 mm drill bit used in a 3 drill technique. The CMC joint was disarticulated after drilling, and cartilage and subchondral bone damage evaluated visually and by gross and microradiographic examination using planimetry. Results: Technique 1 produced significantly more damage of the proximal surface, but significantly less to the subchondral bone of the distal surface. Technique 1 produced the most damage to both the articular cartilage and subchondral bone of the total CMC joint than either of the 3 drill tract techniques; however, the difference between techniques 1 and 2 was not significant. Damage from technique 3 was significantly less than that with techniques 1 or 2. Conclusions: Techniques 1 and 2 produced the most cartilage and subchondral bone damage with technique 2 changes more equally distributed between proximal and distal joint surfaces. Clinical Relevance: Technique 1 (fanning) and 2 (5.5 mm 3 drill tracts) may be preferable to achieve arthrodesis of the CMC joint. Morbidity and efficacy of these arthrodesis techniques need to be evaluated in vivo.     

Diagnostic Methods for Evaluation of Stallion Subfertility: A Review

Classically, evaluation of the breeding stallion for reduced fertility has relied on physical examination of the reproductive system, as well as evaluation of sperm number, motility, and morphology. Over the past 20 years, a number of other diagnostic methods have become available to facilitate reproductive evaluation of the stallion. Specifically, ultrasound imaging has provided much-improved diagnostic methods for evaluation of the external and internal genitalia of the stallion, and these methods have now become routine in evaluation of the stallion. Biochemical analyses of semen can provide useful information for diagnosis of azoospermia (determination of alkaline phosphatase), detection of urine contamination, or changes in pH. Numerous sperm function assays provide information concerning subcellular compartments of the sperm including the plasma membrane, DNA, acrosome, and mitochondria. Data correlating these functional assays with fertility in the stallion are limited in most cases, with the exception of the sperm chromatin structure assay. Finally, the recent sequencing of the equine genome offers the possibility of both marker-assisted selection for fertility traits and more specific information about genetic mutations that may be associated with differing levels of fertility in the stallion.     

Characterization of monoclonal antibodies assigned to the CD45 subgroup of the Third International Swine CD Workshop.

As a result of the first-round cluster analysis, a panel of 16 novel monoclonal antibodies (mAbs) was assigned for detailed analysis to the CD45 subgroup of the Third International Swine CD Workshop. The specificity of the mAbs was initially determined by examining their reactivity with Chinese hamster ovary (CHO) cells engineered to express individual isoforms of porcine CD45. These analyses indicated that seven of the mAbs (PG77A, PG96A, PG167A, PGB78A, 3C/9, MIL13, NHT 101) recognized the portion of the CD45 molecule encoded by the A exon (CD45RA), while one (MIL15) was specific for that portion encoded by the C exon (CD45RC). In each case, the designation was supported by the demonstration that the molecular weight(s) of the recognized antigen(s) in porcine mononuclear cells, as determined by immunoprecipitation, corresponded to the predicted size(s) according to their specificity. As expected, a similar correlation was obtained for five standard mAbs whose specificity for either common or restricted epitopes of porcine CD45 had been established in previous workshops. Screening of the remaining 174 mAbs that comprised this workshop but were excluded from the CD45 subgroup by cluster analysis failed to detect any additional ones reactive with the porcine CD45-expressing cells.     

Bovine Campylobacteriosis: A Review

Campylobacteriosis (vibriosis) is a venereal disease of cattle caused by the organism Campylobacter fetus subspecies fetus previously known as Vibrio fetus subspecies venerealis. Characteristically the disease causes infertility in the female with an increased number of services necessary for conception. Abortions late in gestation are also occasionally seen. Most cases or outbreaks occur after the recent introduction of an infected bull or cow into a susceptible breeding herd. Often the disease remains undetected until late fall when the livestock owner recognizes that he has a number of females exhibiting estrus. A tentative diagnosis can be made by a study of the herd history and can often be confirmed by laboratory means.

In recent years many advances have been made towards establishing an understanding of the immune response that occurs with infection and systemic immunization. In this review, recommendations are made regarding the appropriate time to immunize the breeding herd against campylobacteriosis.