OSTEOCHONDROSIS IN THE LATERAL FEMORAL CONDYLES OF A HORSE

Osteochondrosis of the lateral femoral condyles was diagnosed radiographically in an 8-month-old, female Arabian horse, which had been presented with a hindlimb lameness. The diagnosis was confirmed by gross and microscopic pathology. The location of the lesions was considered unusual for osteochondrosis in the horse.     

Arthrotomy for the treatment of chronic purulent septic gonitis with subchondral osteolysis in two calves

Abstract

CASE HISTORY: A 6-week-old German Holstein heifer calf (Case 1) and a 4-week-old Charolais bull calf (Case 2) were referred because of unilateral hind limb lameness. Both had been treated with systemic antibiotics by the referring veterinarian.

CLINICAL FINDINGS AND DIAGNOSIS: Based on the results of clinical, radiographic and ultrasonographic examination, a diagnosis of chronic purulent septic gonitis with subchondral osteolysis of the lateral femoral condyle was made in both calves. In Case 2 the lateral tibial condyle also showed osteolysis.

TREATMENT AND OUTCOME: Treatment consisted of arthrotomy with debridement of abnormal bone and cartilage via a craniolateral and a caudolateral approach. Case 1 was discharged from with grade 1/5 lameness 60 days after surgery. In a follow-up 15 months postoperatively, the owner reported that it had been bred at 14 months, was not lame and the affected stifle joint appeared normal. Case 2 had grade 2/5 lameness 52 days after surgery, but was sound at the time of slaughter at 22 months of age.

CLINICAL RELEVANCE: Arthrotomy via a caudolateral approach is a suitable method for the treatment of septic purulent gonitis with osteolysis of the lateral femoral and tibial condyles in calves. In these cases, this treatment resulted in the elimination of localised inflammation, prevented clinically relevant spread of infection to other organs, and restored normal joint function.     

Arthroscopic-assisted management of osteochondritis dissecans in the stifle of a cat

An 11-month-old, male neutered, domestic short-haired cat presented for evaluation of sudden onset right pelvic limb lameness. Radiography showed features consistent with unilateral osteochondritis dissecans (OCD) of the lateral femoral condyle in the right stifle. Arthroscopic examination of the stifle was used to confirm the presence of an articular cartilage lesion and the presence of loose cartilage within the joint. The loose cartilage fragments were removed arthroscopically. One arthroscopy portal was extended into a limited arthrotomy, which was necessary to ensure complete debridement of the defect. Removal of the fragments led to complete resolution of the clinical signs. This case report documents a more minimally invasive technique for the management of stifle OCD in the cat than previously documented and helps to establish a protocol for arthroscopic surgery in the feline stifle.     

Bilateral stifle osteochondritis dissecans in a cat

A 9-month-old, castrated male, domestic shorthaired cat was presented for progressive right hind-limb lameness. A diagnosis of osteochondritis dissecans of the lateral femoral condyle was made based on radiographs and physical examination, and was confirmed by right lateral stifle arthrotomy. The cartilage flap was removed, and the underlying bone was curetted. Seven months later, the cat was sound on the right leg but developed a left hind-limb lameness. A similar lesion was found in the left leg and was treated identically. Fourteen months after presentation, the cat was sound on both hind limbs.     

Progression of Femoropatellar Osteochondrosis in Nine Young Horses Clinical, Radiographic and Arthroscopic Findings

The clinical and radiographic progression, and arthroscopic findings for nine young horses (<1 year of age) with femoropatellar osteochondrosis (OCD) are presented. Horses had a 2 to 12 week history of bilateral (8 horses) or unilateral (1 horse) hindlimb lameness. The most consistent clinical signs included femoropatellar joint distention and bilateral hindlimb lameness. At the onset of clinical signs, radiographic lesions were not present (4 horses) or subtle (5 horses), but were easily identified on radiographs taken 4 to 24 weeks later. Arthroscopic surgery was delayed until radiographic changes became obvious. Surgical findings in 20 femoropatellar joints were most commonly osteochondral "flaps" located on the proximal lateral trochlear ridge of the femur and were larger than had been indicated by the radiographs. Eight horses were being used for their intended purpose, which was racing (3 horses were racing and 3 were in race training), dressage (1 horse) or pleasure riding (1 horse). One horse required a second surgery when similar lesions developed in the opposite stifle, and was euthanatized 2 months later because of persistent lameness. Once clinical signs are observed, osteochondrosis lesions of the distal femur can progress in foals younger than 9 months of age and the full extent of the radiographic lesion may take several weeks to develop.     

Case Report of a Complex Lateral Femorotibial Joint Injury With Popliteal Tendonitis in a Foal

A two-month-old, Spanish breed, foal was referred with right hind limb lameness of two weeks duration. Clinical examinations confirmed a complex combination of lesions within the lateral femorotibial joint, including a subchondral bone cyst in the lateral femoral condyle, a severe popliteal tendonitis, and a delayed cartilage detachment of the lateral femoral condyle. Because of the complex association of these lesions, poor prognosis for an athletic career was given to the owner. Four years later, the filly is pasture sound. Lesions of the popliteal tendon in the horse are uncommon. The popliteal tendon should also be investigated in cases of trauma to the lateral femorotibial joint, as it could be associated with other affected structures.     

Effects of porcine zona pellucida immunocontraceptives in zoo felids.

Methods of contraception are necessary for management of zoo felids; however, the most commonly used contraceptive (melengestrol acetate implant) is associated with serious adverse reactions with long-term use. Porcine zona pellucida (pZP) vaccines are promising as contraceptives, but their safety in zoo felids has not been tested. pZP vaccine was administered to 27 female felids representing 10 species, including African lion (Panthera leo), Asian leopard (P. pardus), jaguar (P. onca), tiger (P. tigris), snow leopard (P. uncia), cougar (Felis concolor), Siberian lynx (F. lynx), Canada lynx (F. canadensis), serval (F. serval), and bobcat (F. rufus), in 15 facilities. Over 6 wk, each animal received three i.m. injections of 65 microg pZP with Freund's complete adjuvant (FCA), Freund's incomplete adjuvant, or carbopol as the adjuvant. Behavioral signs of estrus were seen in 14 of the vaccinated felids. An unacceptably high incidence of adverse reactions was seen including injection site swelling, lameness, limb swelling, or abscessation (or all) in five felids after injection with FCA as the initial adjuvant. Adverse behavioral signs, including increased irritability and aggression, were seen in four felids. Six of the felids were assayed for antibodies against pZP during the 12 mo after vaccination; all showed antibody production. Antibody levels appeared to peak 1-4 mo after vaccination began, although elevated antibody levels persisted in two animals for > 12 mo after the first injection. All vaccinated felids were ovariohysterectomized 3-13 mo after vaccination. Folliculogenesis was present in all treated animals, and there was no histopathologic evidence of inflammatory damage to ovaries. Contraceptive efficacy was not specifically evaluated in this study; however, two of the three felids housed with an intact male became pregnant during the study, one of which gave birth to healthy cubs.     

Multiple ocular colobomas in the snow leopard (Uncia uncia)

Two singleton female snow leopard cubs are reported with bilateral central upper lid colobomas. In addition, one cub had a coloboma of the fundus in one eye extending from the lower optic disc region. Surgical treatment by wedge resection was successful in both cases. Details of ocular colobomas in other snow leopards reported in the literature are described and it is suggested that the exact etiology of the condition in this species may be discovered by further study of similar colobomas in the domestic cat.     

Subchondral cystic lesions (osteochondrosis) of the femoral heads in a horse

Bilateral subchondral cystic lesions of the femoral head in a horse resulted in lameness. The lesions had resulted in degenerative disease in the left coxofemoral joint. The cause of lameness was confirmed by use of intra-articular anesthesia, joint fluid analysis, and radiography. Subchondral cystic lesions involving the femoral head should be considered in the differential diagnosis of equine lameness localized in the upper portion of the hind limb.     

Mapping of donor and recipient site properties for osteochondral graft reconstruction of subchondral cystic lesions in the equine stifle joint

REASONS FOR PERFORMING STUDY: To improve osteochondral graft reconstruction of subchondral cystic lesions in the medial and lateral femoral condyles by matching the material properties of donor and recipient sites. OBJECTIVES: To measure biomechanical and biochemical parameters that influence the function and healing of osteochondral grafts used to reconstruct subchondral cystic lesions. HYPOTHESIS: Suitable donor sites are available within the stifle joint for reconstructing the femoral condyles, despite considerable regional property variation. METHODS: Fifty-six osteochondral cores were harvested from 6 distal femurs for initial studies that determined subchondral bone modulus of elasticity and ultimate stress. In a second study, 28 osteochondral cores were harvested from 6 distal femurs to measure cartilage aggregate modulus, thickness and sulphated glycosaminoglycan (sGAG) content. Using micro-CT imaging, subchondral bone mineral density and bone volume fraction were also measured. In both studies 2-dimensional contour plots using a bicubic interpolation method and normalised data were generated to allow visual comparison of joint surface characteristics. Statistical comparisons between donor and recipient site raw data were made using an ANOVA for repeated measures with a post hoc Tukey test. RESULTS: Material properties of cartilage and bone vary considerably over the surface of the stifle joint but the central region of the medial condyle, where subchondral cystic lesions freqdently occur, typically demonstrated bone strength and modulus values of the highest observed. Cartilage thickness and aggregate modulus were highest in the medial femoral condyle and axial aspect of the lateral condyle. CONCLUSIONS: Material properties of the grafts from the trochlear groove and axial aspect of the lateral trochlear ridge were the closest match for those found in the medial condyle, whereas properties of the lateral condyle were most similar to those found in the trochlear groove and axial aspect of the medial trochlear ridge.     

Lateral glenohumeral ligament rupture in three dogs

Three adult large breed dogs were evaluated for chronic forelimb lameness. Clinical examination localised pain to the area of the shoulder joint. Traditional imaging methods, including radiography, arthrography and ultrasonography, were unrewarding. Arthroscopy performed via a lateral portal demonstrated complete tears of the proximal part of the lateral glenohumeral ligament in all cases. Two of the three cases responded to treatment with intra-articular methylprednisolone and rest with a resolution of the lameness, while the third failed to improve. Surgical intervention in this third case involved lateral capsulorraphy, and re-examination at five weeks postoperatively showed the dog to be without lameness. Tearing of the lateral glenohumeral ligament should be considered in the differential diagnosis of shoulder lameness. Surgical stabilisation should be considered in cases refractory to conservative treatment.     

GROSS AND HISTOPATHOLOGIC CORRELATION OF LOW‐FIELD MAGNETIC RESONANCE IMAGING FINDINGS IN THE STIFLE OF ASYMPTOMATIC HORSES

With the recent introduction of a 0.25T rotating MRI system, clinical evaluation of the equine stifle joint is now possible in the average equine athlete. A recent publication described common abnormalities of horses with stifle lameness detected with a low‐field MRI system; however, postmortem corroboration of the lesions detected was not possible. Therefore, our objective was to compare postmortem findings with low‐field MRI findings in equine cadaver stifle joints. Ten fresh cadaver stifle joints from horses without clinical signs of stifle disease were evaluated using low‐field MRI, gross dissection, and histopathology. In eight stifles, either the lateral or medial cranial meniscotibial ligament had an irregular shape, fiber separation, or moderate abnormal signal intensity (SI) on all sequences. In five stifles, the medial femoral condyle had articular cartilage fibrillation with or without an osteochondral defect over the weight bearing surface of the medial femoral condyle. All stifles had abnormal SI on all sequences within the patellar ligaments that corresponded with adipose tissue infiltrating between the collagen bundles. Other abnormalities identified included articular cartilage fibrillation of the tibial condyles in three stifles, and articular cartilage fibrillation with chondral defects in the patella in three stifles. All abnormalities detected with low‐field MRI were corroborated by gross dissection. Findings from the current study supported the use of low‐field MRI for detection of stifle joint lesions in horses and demonstrated that some stifle joint pathologies may be subclinical in horses.     

Osteochondritis dissecans-like lesion of the intercondylar fossa of the femur in a dog.

An 11-month-old neutered female crossbreed dog was admitted with left pelvic limb lameness. Radiographs and computed tomography identified an osteochondritis dissecans- (OCD) like lesion in the intercondylar fossa of the femur originating from the axial aspect of the medial femoral condyle. Stifle arthrotomy was performed in order to remove the bony fragment. It was concluded that the clinical features and location of this lesion indicate an osteochondritis dessicans-like lesion. Fragment removal was associated with an excellent outcome.     

Femoral Head Osteotomy in Horses and Cattle

Femoral head ostectomy was performed in six horses, three ponies, and four cattle for treatment of fractures of the femoral capital physis, coxofemoral luxation, fractured acetabulum, or severe degenerative joint disease. The procedures were performed via a cranial approach that did not involve osteotomy of the greater trochanter. A dorsal approach for femoral head ostectomy via osteotomy of the greater trochanter was evaluated in three healthy adult ponies. Three animals (2 ponies, 1 calf) were euthanatized within a month and one horse was euthanatized at year 2 due to postoperative complications. Nine animals were discharged to owners and six of them fulfilled their intended functions of breeding, milking, and being kept as companions. One horse was lost to follow-up and two horses died of causes unrelated to the surgery. All surviving animals had a residual lameness that was described by owners as mild to moderate. None of the horses were used as riding animals. The mean age and weight of 10 animals that regained weight-bearing locomotion was 3.1 months and 84 kg; for three unsuccessful cases it was 34 months and 174 kg. We concluded that femoral head ostectomy was a viable salvage procedure for large animals with capital femoral physeal fracture, chronic coxofemoral luxation, or acetabular fracture. Surgical prognosis appeared to be favorable in young cattle and fair in young horses or ponies weighing less than 100 kg. Osteotomy of the greater trochanter resulted in superior exposure of the intact coxofemoral joint and allowed easier, less traumatic surgical luxation of the joint to facilitate femoral head ostectomy.     

Radiographic features of two cases of feline proximal femoral dysplasia

Congenital or acquired feline femoral dysplasia have seldom been reported in the literature. This report describes two cases of femoral dysplasia involving the proximal epiphyses. Bilateral agenesis of the femoral head and neck (case 1) constituted an incidental finding during a post-traumatic radiographic examination, while right proximal femoral dysplasia (case 2) was observed during an orthopaedic examination for lameness. To the authors' knowledge, such imaging findings have not been reported before in cats.     

Distribution of lameness lesions in beef cattle: A retrospective analysis of 745 cases

The objective of this retrospective study was to characterize the relative prevalence of diagnoses and location of lameness lesions in beef cattle. Medical records from 2005 to 2012 were reviewed and 745 cases of beef cattle that had presented for lameness were identified. Information regarding signalment, lesion location, and cause of lameness was analyzed. The cause of lameness was localized to the foot in approximately 85% of cases; a hind limb was affected over 70% of the time. The lateral claw was most commonly affected in cases of both fore- and hind-limb lameness. The most common diagnoses of noninfectious etiology were screw claw, vertical fissure, and interdigital fibroma. Infectious foot disease accounted for only 20% of foot lameness. Routine foot trimming may be warranted in some herds to improve weight-bearing balance and alleviate lameness.     

Tibiotarsal arthroscopy. Applications and long-term outcome in dogs.

The objective of this retrospective article was to describe the use of, and to determine long-term outcome of, tibiotarsal arthroscopy in dogs. The medical records of 20 client-owned dogs with tibiotarsal joint disease with arthroscopic treatment were reviewed. Long-term follow-up evaluation of lameness, force plate gait analysis, and radiographs to assess progression of degenerative joint disease (DJD) were performed. Arthroscopy was utilized in the diagnosis of talar osteochondritis dissecans (OCD), collateral ligament injury, septic arthritis, immune mediated arthritis, and a distal talar fragment. Sixteen joints with OCD treated resulted in 10/14 dogs with lameness after exercise only, progression of DJD in most cases, and chronic lameness when comparing operated to unoperated limbs with force plate evaluation at a mean follow-up of 35 months. Following treatment, three dogs with collateral ligament injury had reduced weight bearing on the operated limb, radiographic progression of DJD, and minimal lameness at a mean follow-up of 27 months. Tibiotarsal arthroscopy can be successfully used to help diagnose, and often to treat: OCD, collateral ligament injury, fractures, septic and non-septic arthritis in the dog. The minimally invasive nature of arthroscopy preserved joint stability while allowing complete examination of the articular cartilage. In most cases long term tibiotarsal DJD advancement was the rule.     

Bone marrow lesions of the distal condyles of the third metacarpal bone are common and not always related to lameness in sports and pleasure horses

The metacarpophalangeal joint is a common site of pain in horses. Little information is available about bone marrow lesions in the distal condyles of the third metacarpal bone in sports and pleasure horses. Aims of this prospective, retrospective, observational study were to evaluate the prevalence of bone marrow lesions in the distal condyles of the third metacarpal bone, to describe their anatomic distribution and to correlate lesions with the presence of lameness and the level and type of activity. All sports and pleasure horses undergoing standing low‐field MRI of the front fetlock region between 2009 and 2016 were included and divided into three lameness groups according to the results of diagnostic analgesia. Bone marrow lesions were analyzed and graded by one reader. Grades were compared between anatomical locations and between lameness groups. A total of 166 horses were sampled. The prevalence of bone marrow lesions was 76.5% (127/166). The dorsal aspects of the medial condyle (31%, 39/127) and of the sagittal ridge (28%, 36/127) were the most commonly affected locations. There was no significant difference between both forelimbs (lame limb and non‐lame limb) of the same horse. Lesion severity was neither significantly associated with the lameness group nor with the type or level of activity. The prevalence of bone marrow lesions in the distal condyles of the third metacarpal bone is high in this population and the clinical significance is not always clear. Further studies are required to elucidate the clinical significance of this finding in sports and pleasure horses.     

Osteochondritis dissecans of the lateral ridge of the trochlea of the tibial tarsal bone in the dog

The diagnosis and treatment of two cases of osteochondritis dissecans affecting the lateral ridge of the trochlea of the tibial tarsal bone is described. Radiographs taken in medio-lateral and oblique projections proved to be the most valuable for diagnosis. The lesions were treated surgically via a limited cranio-lateral approach. The lameness improved following surgery.