Experimental Coxofemoral Replacement Hemiarthroplasty in the Pony

For the in vivo evaluation of hip joint prostheses that are developed for man, the suitability of the pony as an animal model has been studied. Human and custom made prostheses were implanted into 1 femur in each of 7 ponies to replace the femoral head. The surgical approach was through a caudolateral incision. The prosthesis was fixed in the femur with bone cement. Because of errors in the implantation technique and resulting lack of sufficient fixation 2 ponies as well as 1 control animal with an excision arthroplasty were unwilling or unable to stand. Rigid fixation of the implant was achieved in 3 ponies. They were returned to pasture after 8 days. A full return to a normal gait did not occur within an observation period of up to 3 months. All 3 ponies developed a dorsolateral coxofemoral luxation and pseudarthrosis within the first 10 days. A mismatch between the equine anatomy and human prosthesis geometry was thought to be the cause. We, therefore, believe that the pony does not provide a suitable model for the testing of human femoral joint implants. The results, however, indicate that coxofemoral surgery can be performed in the adult pony. For clinical reconstruction of joint function, a custom made total artificial hip joint might provide better results.     

Fate and effect of autogenous osteochondral fragments implanted in the middle carpal joint of horses.

Four autogenous osteochondral fragments removed from the lateral trochlear ridge of the talus were arthroscopically placed as loose bodies in a randomly selected middle carpal joint in each of 10 horses. The contralateral middle carpal joint, subjected to a sham procedure, served as control. Postoperative treatment was consistent with that for clinical arthroscopic patients. Lameness evaluation, radiographic examination, carpal circumference measurement, and synovial fluid analysis were performed before and at scheduled intervals after surgery. After a 2-month confinement, horses were subjected to an increasing level of exercise. Horses were euthanatized at intervals through 6 months. Gross and microscopic evaluations were performed on remaining fragments, articular cartilage, and synovial membrane of each middle carpal joint. Increased joint circumference, effusion, lameness, and degenerative joint disease distinguished implanted from control joints over the 6-month period. Implanted joints were characterized by grooved, excoriated cartilage surfaces, and synovium that was thick, erythematous, and irregular. At 4 weeks, implants were found to have adhered to synovium at their subchondral bone surface. The bone within fragments was undergoing necrosis, while cartilage was preserved. At 8 weeks, fragments were radiographically inapparent, grossly evident as pale plaques on the synovial surface, and composed of dense fibrous connective tissue. Synovial membrane specimens from implanted joints had inflammatory change characterized by mononuclear cell infiltration 2 months after implantation. Physical damage was apparent within articular cartilage of implanted joints at 2 months, and was significant (P less than 0.05) at 6 months after surgery. Chondrocyte degenerative change was significant (P less than 0.05) at 6 months after surgery. Focal reduction in safranin-O uptake was observed in cartilage layers adjacent to physical defects. Osteochondral loose bodies of the size implanted in the middle carpal joint of horses in this study were resorbed by the synovium within 2 months. Synovitis and significant articular cartilage damage were associated with the implanted fragments. Regardless of origin, free osteochondral fragments within the middle carpal joint should be removed, and methods to prevent residual postoperative debris should be implemented to reduce potential for articular pathologic change.     

Augmentation of the transverse acetabular ligament in canine caudoventral hip luxation.

Open surgical fixation was performed on four hip joints in three dogs who were suffering from caudoventral hip luxations for which closed reduction had previously failed. Stabilization of the joint was achieved with a ventral coxofemoral approach, which augmented the function of the transverse acetabular ligament using a sling implant through a bone tunnel (n = 1), a sling implant around two pelvic screws (n = 1), or an internal fixator plate (n = 2). Transverse acetabular ligament augmentation resulted in successful joint stabilization in all cases, and should be considered for the surgical reduction of caudoventral hip luxations in dogs. The use of an internal fixator plate, while preserving soft-tissue blood supply and resulting in minimal to no long-term arthritic changes, may provide an optimal outcome.     

Hind limb kinematics during therapeutic exercises in dogs with osteoarthritis of the hip joints

Objective-To assess joint kinematics in dogs with osteoarthritis of the hip joints during walking up an incline or down a decline and over low obstacles and to compare findings with data for nonlame dogs. Animals-10 dogs with osteoarthritis of the hip joints (mean ± SD age, 6.95 ± 3.17 years; mean body weight, 34.33 ± 13.58 kg) and 8 nonlame dogs (3.4 ± 2.0 years; 23.6 ± 4.6 kg). Procedures-Reflective markers located on the limbs and high-speed cameras were used to record joint kinematics during walking up an incline or down a decline and over low obstacles. Maximal flexion, extension, and range of motion of the hip joints were calculated. Results-Osteoarthritis of the hip joints reduced extension of both hip joints and flexion of the contralateral hind limb, compared with flexion of the lame hind limb, during walking down a decline. Walking up an incline resulted in decreased extension of the stifle joint in both hind limbs of osteoarthritic dogs; extension was significantly decreased for the lame hind limb. During walking over low obstacles, maximal flexion of the stifle joint was increased significantly for the contralateral hind limb. Maximal flexion was increased in both tarsal joints. Conclusions and Clinical Relevance-Osteoarthritis of the hip joints led to complex changes in the gait of dogs, which involved more joints than the affected hip joint alone. Each exercise had specific effects on joint kinematics that must be considered when planning a rehabilitation program.     

Comparison of measurements of dorsolateral subluxation of the femoral head and maximal passive laxity for evaluation of the coxofemoral joint in dogs

OBJECTIVE: To determine whether dorsolateral subluxation (DLS) of the femoral head reflects osseous conformation of the coxofemoral (hip) joint and represents a property distinct from maximum passive laxity of the hip joint in dogs. ANIMALS: 14 Labrador Retrievers, 16 Greyhounds, 58 Greyhound-Labrador Retriever mixed-breed dogs, and 1 Rottweiler. PROCEDURES: DLS of the femoral head (DLS score) and passive laxity of the hip joint (distraction index) were determined radiographically in 3 groups of dogs: not treated (167 joints of 84 dogs); before and after injecting 2 ml of hyaluronan into 25 hip joints of 13 dogs; and before and after unilateral triple pelvic osteotomy in 5 dogs. Results of the 2 methods were compared for each group. RESULTS: In untreated dogs, the correlation coefficient (r) of DLS score versus distraction index was -0.73 and -0.69 for 84 left and 83 right hip joints, respectively. Mean coefficient of determination (r2) for both hips was 0.5. Mean DLS score did not differ before and after intra-articular injection of hyaluronan into either hip joint, whereas mean distraction index increased significantly after intra-articular injection. Unilateral triple pelvic osteotomy resulted in a significant increase in DLS score, compared with values obtained before surgery. However, distraction index before and after surgery did not differ significantly. CONCLUSIONS AND CLINICAL RELEVANCE: The DLS test assesses the congruity of the acetabulum and the femoral head in a canine hip joint and thus represents a characteristic distinct from maximum passive laxity. The DLS score and the distraction index evaluate different components of hip joint stability.     

Effect of anaesthesia and stress on the radiographic evaluation of the coxofemoral joint

A pelvic radiographic examination was performed on 15 large breed dogs without history and clinical sign of hip dysplasia. The effect of anaesthesia and of two stress-radiographic methods on the coxofemoral subluxation was evaluated. With anaesthesia a mild coxofemoral subluxation was seen in 31 per cent of the dogs, which all appeared radiographically normal when sedated. The Norberg angle was significantly decreased in anaesthetised dogs (P < 0–05). When dogs with a radiographically normal coxofemoral joint conformation were submitted to a stress-radiographic examination there was a shift towards an increased coxofemoral subluxation. Subluxation was seen in 70 per cent of the dogs when the knee fixation method of positioning was applied and in 100 per cent of the dogs when the wedge method was used. Correspondingly the Norberg angle decreased significantly when the coxofermoral joints were stressed (P_kneefix < 0–00003; P_wedge= 0–000008). The study concludes that the currently used procedure for evaluation of the hip joints does not necessarily disclose whether or not a dog has hip dysplasia.     

Relationships between results of the Ortolani method of hip joint palpation and distraction index, Norberg angle, and hip score in dogs

OBJECTIVE: To determine whether results of the Ortolani method of hip joint palpation in dogs were related to distraction index (DI), Norberg angle, or radiographic hip score. DESIGN: Cross-sectional study. ANIMALS: 459 clinically normal dogs. PROCEDURE: Dogs were sedated for radiography and palpation of the hip joints. Results of hip joint palpation were classified as negative, mild positive, moderate positive, or severe positive. Distraction indices were measured for all dogs. Norberg angles were measured for 380 dogs for which ventrodorsal hip-extended radiographic projections were available. Hip scores assigned by the Orthopedic Foundation for Animals (OFA) were available for 95 dogs. RESULTS: Age, weight, and sex were not significantly associated with results of hip joint palpation. There was moderate correlation between results of hip joint palpation and DI (r = 0.636), low-moderate correlation between results of hip joint palpation and OFA hip scores (rs = 0.437), and weak negative correlation (r = -0.236) between results of hip joint palpation and Norberg angle. For joints without degenerative joint disease (DJD), there was a significant linear relationship between results of hip palpation and DI; however, for joint with DJD, there was not. Results of hip joint palpation were 5.3-fold as likely to be negative for dogs with DJD as for dogs without. CLINICAL IMPLICATIONS: Results of hip joint palpation were at best moderately correlated with radiographic measures of hip joint laxity. Therefore, hip joint palpation should be combined with hip-extended and stress radiography when assessing hip joint quality.     

Computed tomographic evaluation of growth-related changes in the hip joints of young dogs

OBJECTIVE: To evaluate changes in canine hip joint characteristics during growth via computed tomography (CT) and compare CT features of hip joints with and without laxity in young dogs placed in 2 imaging positions. ANIMALS: 21 dogs (42 hip joints). PROCEDURES: From 2 to 12 months after birth, CT examinations of the acetabulum of each hip joint in simulated normal standing and simulated weight-bearing positions were performed monthly for all dogs. Acetabular angle, dorsal acetabular rim angle (DARA), and femoral head diameter (FHd) were analyzed as skeletal variables; the lateral center edge angle (LCEA), dorsolateral subluxation (DLS) score, and center distance (CD) index were analyzed as joint laxity variables. At 12 months, all dogs underwent the Ortolani test to as-sess hip joint laxity. RESULTS: Hip joint laxity was detected in 5 dogs (10 joints) at 12 months of age; from 2 months, the acetabular angle and FHd increased and DARA decreased significantly until 5 months and the LCEA and DLS score increased significantly until 6 months. In nonlax hip joints in both positions, the CD index decreased significantly until 4 months of age and be-came stable thereafter. In lax hip joints, the CD index increased from 4 through 12 months; between 8 and 12 months, these changes were significantly greater in the weight-bearing position than in the standing position. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that CT-detected abnormalities in the DARA and CD index during body weight loading might be useful indicators of hip dysplasia in 2- to 6-month-old dogs.     

Ultrasound-guided coxofemoral arthrocentesis in horses

REASON FOR PERFORMING STUDY: Coxofemoral joint pain is probably underestimated due to difficulties in identifying hip pain. The deep location of the joint and proximity of the sciatic nerve make arthrocentesis based on external landmarks a difficult and potentially risky procedure in mature horses. OBJECTIVES: To describe an ultrasound-guided injection technique of the coxofemoral joint in standing horses and to evaluate its accuracy and potential difficulties/complications. METHODS: Nine mature horses had both pelvic areas prepared for sterile ultrasound examination (3.5 MHz curvilinear probe). Coxofemoral joints were located and penetrated at their craniodorsolateral aspect under ultrasonographic guidance and injected with sterile contrast medium. A standing ventrodorsal radiographic view of each hemipelvis centred on the hip was obtained for each horse to assess the injection site. Horses were evaluated for 10 days following injection for possible complications. RESULTS: Intra-articular injection was successful in all 18 joints. The procedure was well tolerated by horses under minimal restraint. Mean +/- s.d. needle repositionings required before accurate placement was 1.5 +/- 1.3 per joint. Once the needle was in the joint, synovial fluid was obtained in 7/18 joints. Minimal periarticular contrast medium was detected in 2/18 joints. Mean +/- s.d. ultrasonographic examination time required for coxofemoral localisation, accurate needle positioning and injection was 4.3 +/- 2.1 min. No complications were observed in the 10 days following injection. CONCLUSION: The ultrasound-guided coxofemoral arthrocentesis is an accurate, reliable and safe technique that offers a real time evaluation of needle introduction into the deep and narrow coxofemoral joint space. POTENTIAL RELEVANCE: Although this technique remains to be tested on clinical cases, it is a promising tool to facilitate diagnosis of coxofemoral pain, septic arthritis or administration of intra-articular medication.     

Canine hip dysplasia: study of heritability in 401 litters of German Shepherd dogs

Heritability of hip dysplasia was estimated to be about 0.4 to 0.5 when based on the radiographic evaluations of the hip joints of 2,404 German Shepherd Dogs born at The Armed Forces Dog Training Center in Sweden. The material included all dogs in 401 litters born at the Center from 1965 through 1973 that reached the age of 15 months. To be expected with such high heritability, frequency of hip dysplasia in the offspring was shown to be affected by the hip joint status of sire and dam as well as by the hip joint status of their parents and littermates. Even matings between sires with normal hip joints and dams with only slight dysplasia resulted in significantly higher frequency of hip dysplasia in the offspring, when compared with the frequency if both sires and dams had normal hip joints. Frequency of hip dysplasia in the progeny of sires with normal hip joints varied greatly. Since 1973, selection of the breeding stock has been based on hip joint status (phenotype) of the breeding animals and of their relatives as well as on what had become known about frequency of hip dysplasia in the litters already born (progeny testing). In this way, frequency of hip dysplasia in 347 dogs born at the Center during 1975 was lowered to 28%. This figure should be compared with the figure of 50%, which represents the frequency of hip dysplasia in the kennel up to 1970, when selection was not as strict as could be expected in a well-controlled kennel.     

Evaluation of samarium-153 for synovectomy in an osteochondral fragment-induced model of synovitis in horses

OBJECTIVE: To determine the effects of intraarticular administration of Samarium-153 (153Sm) bound to hydroxyapatite microspheres (153SmM) on an osteochondral chip-induced synovitis. STUDY DESIGN: Sixty days after implantation of autogenous osteochondral fragments in the middle carpal and metacarpophalangeal joints, 153SmM was administered into 1 joint of each type. The contralateral joints were used as untreated controls. ANIMALS OR SAMPLE POPULATION: Fifteen horses without preexisting joint disease were randomly divided into 2 groups (7 in the carpal group, 8 in the metacarpophalangeal group). METHODS: Horses had osteochondral fragments that were harvested from the lateral ridge of the trochlea of the talus and implanted bilaterally into a middle carpal joint and a metacarpophalangeal joint; the opposite joint type served as a control. Sixty days later, 10 to 15 mCi of 153SmM (20 to 50 microm diam) was injected into the fragment-implanted joints. Three horses were treated with nonradioactive hydroxyapatite fragments. Horses were examined clinically until they were killed 14 or 30 days later. Control and treated joints were examined grossly and microscopically to determine the effects of 153SmM on synovial membrane and cartilage. RESULTS: Intraarticular 153SmM caused a transient flare with lameness, effusion, and edema for 48 to 72 hours. Implanted osteochondral chips induced a synovitis characterized by variable degrees of joint damage and synovial infiltrate. Use of 153SmM resulted in synovectomy of variable depth and extent. CONCLUSIONS: Intraarticular 153SmM may be a useful method for synovectomy of inflamed synovial membrane. CLINICAL RELEVANCE: With further testing, radioactive pharmaceuticals might become useful clinical treatments for persistent synovitis not responsive to conventional techniques.     

Transmission of relaxin and estrogens to suckling canine pups via milk and possible association with hip joint laxity

OBJECTIVE: To determine whether abnormal laxity of hip joints of canine pups with genetic predisposition to hip dysplasia (HD+) is related to ingestion of milk-borne hormones. ANIMALS: 7 female Labrador Retrievers with HD+ and 8 with low predisposition to hip dysplasia (HD-) and their offspring. PROCEDURES: Immunoactive relaxin, estrogen, and estrogen precursor concentrations in milk of HD+ lactating bitches and in serum of their pups were compared with those of HD- bitches and pups. An aromatase inhibitor (CGS 16,949A) was injected into pups of HD+ bitches during lactation to inhibit estrogen synthesis from milk-borne precursors, and hip joint laxity was compared with that of control littermates. Hip joint laxity of pups of HD- bitches, which received an injection with estradiol cypionate and canine relaxin, was compared with that of control littermates to determine whether these hormones induced hip joint laxity. RESULTS: High concentrations of estrogens and relaxin were found in milk of HD+ and HD- bitches throughout lactation. Serum concentrations of milk-derived relaxin and total estrogens were similar in all pups, but estradiol-17B was detected only in pups of HD+ bitches. Hip joint laxity was reduced in pups that received CGS 16,949A. Hip joint laxity was INCREASED IN PUPS OF HD- BITCHES THAT RECEIVED ESTRADIOL CYPIONATE AND RELAXIN. CONCLUSIONS AND CLINICAL RELEVANCE: Milk-borne maternal hormones and precursors were absorbed into the circulation of canine neonates and may play a role in hip joint laxity in HD+ pups. Phenotypic expression of hip dysplasia may therefore be preventable by antihormone treatment.     

Advances in total joint replacement in small animals

Total joint replacement is now considered a routine surgical option for small animals with advanced joint disease. This review highlights the current state of the art in total hip, elbow and knee replacement in small animals, as well as the potential for application to other joints such as the intervertebral discs, hock and shoulder. Advances in cementless fixation, the use of less-invasive, bone-sparing procedures, and the development of custom implant options for revision surgery and oncologic reconstruction will be discussed. As growth in this field continues, it is important that future developments in total joint replacement are built on a foundation of detailed laboratory evaluation of new implant designs and surgical techniques, objective assessment of clinical outcomes, and a comprehensive, coordinated retrieval program that evaluates both well-functioning and failed joint replacements.     

Effect of trotting velocity on work patterns of the hind limbs of Greyhounds

OBJECTIVE: To quantify the effects of trotting velocity on joint angular excursions, net joint moments, and powers across the hind limb joints in Greyhounds. ANIMALS: 5 healthy Greyhounds with no history of lameness of the hind limbs. PROCEDURES: Small reflective markers were applied to the skin over the joints of the hind limbs, and a 4-camera kinematic system was used to record positional data at 200 Hz in tandem with force platform data while the dogs trotted on a runway at slow, medium, and fast velocities. Breed-specific morphometric data were combined with kinematic and force data in an inverse-dynamics solution for net joint moments and powers at the hip, stifle, tarsal, and metatarsophalangeal joints. RESULTS: Angle, moment, and power patterns at the various joints were conserved among the 3 velocities. With increasing velocity, moments and powers at the tarsal, stifle, and hip joints during the stance phase were increased in amplitude, whereas amplitudes during the swing phase were not. The main contributors to increased velocity were the hip extensors and stifle flexors during the early part of the stance phase and the tarsal extensors during the late part of the stance phase. CONCLUSIONS AND CLINICAL RELEVANCE: Increases in trotting velocity in Greyhounds do not alter the basic patterns of work and power for various joints of the hind limbs, but local burst amplitudes during the stance phase increase incrementally.     

The hindlimb in walking horses: 2. Net joint moments and joint powers

The objective of the study was to describe net joint moments and joint powers in the equine hindlimb during walking. The subjects were 5 sound horses. Kinematic and force data were collected synchronously and combined with morphometric information to determine net joint moments at each hindlimb joint throughout stance and swing. The results showed that the net joint moment was on the caudal/plantar side of all hindlimb joints at the start of stance when the limb was being actively retracted. It moved to the cranial/dorsal side around 24% stride at the hip and stifle and in terminal stance at the more distal joints. It remained on the cranial/dorsal side of all joints during the first half of swing to provide active limb protraction, then moved to the caudal/plantar aspect to reverse the direction of limb motion prior to ground contact. The hip joint was the main source of energy generation throughout the stride. It was assisted by the tarsal joint in both stance and swing phases and by the fetlock joint during the stance phase. The coffin joint acted as an energy damper during stance, whereas the stifle joint absorbed almost equal amounts of energy in the stance and swing phases. The coffin and fetlock joints absorbed energy as the limb was protracted and retracted during the swing phase, suggesting that their movements were driven by inertial forces. Future studies will apply these findings to detect changes in the energy profiles due to specific soft tissue injuries.     

Viscosity determination of synovial fluids from the canine hip and elbow joint as well as the human knee joint

The development of pathological changes in both human and canine hip joints is mainly caused by a lack of synovial fluid lubrication. This results in an increased joint abrasion. Even after implantation of joint prosthesis, inadequate lubrication can lead to abrasion in the tribological pair. This can finally result in aseptic loosening of the prosthesis. In spite of the enormous number of studies that have been performed on human, only little knowledge about the tribological properties of the joints in dogs is available in the literature. For this reason the viscosities of synovial fluid, derived from physiological and pathologically changed canine elbow joints were measured. The viscosities were determined by the use of a cone-plate viscometer at different temperatures and shear rates. The obtained values were compared with the viscosity values of pathologically changed synovial fluids from human knee joints as well as with pathological samples from the canine hip joint. The results show that the viscosity values vary within a series of measurements and are inversely proportional to the temperature of the sample and the shear rate. The differences between the average viscosities of canine and human synovial fluids taken from pathologically changed joints are below 4% (22.5 s(-1) at theta1 = 25 degrees C). The findings of this study are being implemented in a FE-Model for the computation of actual forces in the hip joint during different movements. This would represent a contribution to an improved prosthetic treatment of canine and human hips.     

Evaluation of multiple radiographic predictors of cartilage lesions in the hip joints of eight-month-old dogs

OBJECTIVE: To determine the radiographic methods that best predict the development of osteoarthritis in the hip joints of a cohort of dogs with hip dysplasia and unaffected dogs. ANIMALS: 205 Labrador Retrievers, Greyhounds, and Labrador Retriever-Greyhound crossbred dogs. PROCEDURE: Pelvic radiography was performed when the dogs were 8 months old. Ventrodorsal extended-hip, distraction, and dorsolateral subluxation (DLS) radiographs were obtained. An Orthopedic Foundation for Animals-like hip score, distraction index, dorsolateral subluxation score, and Norberg angle were derived from examination of radiographs. Osteoarthritis was diagnosed at the time of necropsy in dogs > or = 8 months of age on the basis of detection of articular cartilage lesions. Multiple logistic regression was used to determine the radiographic technique or techniques that best predicted development of osteoarthritis. RESULTS: A combination of 2 radiographic methods was better than any single method in predicting a cartilage lesion or a normal joint, but adding a third radiographic method did not improve that prediction. A combination of the DLS score and Norberg angle best predicted osteoarthritis of the hip joint or an unaffected hip joint. All models that excluded the DLS score were inferior to those that included it. CONCLUSIONS AND CLINICAL RELEVANCE: A combination of the DLS score and Norberg angle was the best predictor of radiographic measures in 8-month-old dogs to determine whether a dog would have normal or osteoarthritic hip joints.     

Prosthetic Coxofemoral Joint Replacement in the Goose (Anser Sp.): II. Histologic and Mechanical Interface Evaluations

The interfacial tissue-implant healing reactions have been investigated in the goose to evaluate its suitability as an animal model for joint replacement implant studies. After various implantation periods, geese with one coxofemoral replacement hemiarthroplasty were evaluated for their gait performance and then sacrificed. The implantation sites and femora with implants were subjected to histologic studies, and the interfacial shear strength between the bone and implant was measured. The results were compared with findings reported in the literature on dog and man. Direct bone apposition was found in two geese with a firmly fixed implant. A connective tissue capsule surrounded those seven implant stems that were found to sit loosely in the femoral canal. Whereas the histologic findings were comparable to findings in dog and man, the interfacial shear stress was somewhat lower in the goose. Because of the histopathologically comparable findings of interfacial healing, the goose appears to present a suitable model to study bone implant tissue reactions. Further studies are necessary to determine seasonal-, age-, and sex-related bone tissue differences in the goose.     

The arthrographic presentation of the hip, knee and tarsal joints of the cat]

The purpose of the present paper was to find out the most suitable localizations to puncture of hip, stifle and hock joints of the domestic cat. These joints are arthrographically presented. Further six contrast mediums in normal commercial usage were tested with regard to there contrast intensity. The only recommendable localization to arthrocentesis of the hip joint is at the cranial border of the greater trochanter of the femur. The stifle joint is approachable either at the medial or lateral border of the Lig. patellae. To puncture the proximal row of the hock joint the recommendable puncture site was found distal of the lateral malleolus between the tendons of the lateral digital extensor muscle and m. extensor digitorum longus. Any arthrocentesis of the distal row of the hock joint isn't recommendable. Contrast mediums with a iodine concentration below 300 mg/ml were not sufficient for arthrography.     

Static and dynamic ultrasonography for the early diagnosis of canine hip dysplasia

Objective : To determine the feasibility of sonographical examination of hip joints in non-sedated puppies and to assess the value of static and dynamic ultrasonography for the early diagnosis of canine hip dysplasia (CHD). Methods : Prospective study was carried out. Five hundred and sixty-six puppies between the ages of 16 and 49 days underwent sonographical determination of the α-angle, joint laxity and distraction value (DV). Sonographical parameters were correlated to conventional radiographic CHD classification in the adult dogs. Results : α-Angles between 74° and 89° (X ±sd=82·8°±2·31°) were measured. Despite the feasibility of sonographical hip assessment in puppies, no statistically significant correlation was found between sonographical determinations of the α-angle, joint laxity, DV and conventional radiographic hip joint classification at the age of 12 to 24 months. Clinical Significance : Results of our study suggest that static and dynamic ultrasonography of hip joints in puppies between 16 and 49 days of age is technically feasible but cannot be recommended for detecting puppies that will develop CHD between the ages of 12 and 24 months.