Comparison of the biomechanical properties of rottweiler and racing greyhound cranial cruciate ligaments

An in vitro study of rottweiler and racing greyhound cranial cruciate ligaments revealed that the rottweiler ligaments had a significantly greater cross-sectional area at their distal attachments. Mechanical testing showed that the ultimate load related to body mass was significantly higher in the extended racing greyhound stifle during cranial tibial loading to failure, as were linear stiffness, tensile strength and tangent modulus. During ligament axis loading to failure, the only significant difference in structural and mechanical properties recorded between the two breeds was a greater ultimate strain for the greyhound ligament with the stifle joint flexed. Energy absorbed by the ligament complex at failure during cranial tibial loading was twice that for ligament axis loading for both breeds. The clinical significance is that the rottweiler cranial cruciate ligament is more vulnerable to damage as it requires half the load per unit body mass that the greyhound requires to cause a rupture.     

Osteochondromatosis in the racing greyhound

This paper describes the occurrence of osteochondromatosis (OCM) in the distal radius of the right forelimb of two racing Greyhounds. Both cases were presented with right forelimb lameness. In case 1, the OCM was secondary, while in case 2, it was the primary cause of lameness. Surgery and histopathology were performed on case 2. Both cases won races after their respective treatments.     

Metatarsal III fractures in the racing greyhound

During a five-year period, six single stress fractures of metatarsal Iii fractures were diagnosed in five greyhounds. All cases occurred while racing and without external trauma. Treatment by external support had previously been unsuccessful in three cases. However, surgical treatment permitted a prompt return to racing in all cases treated. The aetiopathogenesis of these fractures, the relative importance of the functional anatomy of the canine hock and the practice of racing greyhounds around tight curves are discussed.     

Toe and muscle injuries of the racing greyhound

Extract

The popularity of greyhound racing continues to climb in whichever country or stateit has been introduced. Following the introduction of the Totalisator Agency Board (T.A.B.) to produce off-course legalized betting in Australia, greyhound racing has boomed to unparalleled heights. Further, the additional prizemoney now available to the successful greyhound owner has attracted owners who were previously interested only in horse racing.     

Central tarsal implant in a racing greyhound

Although most type IV fractures in dogs can be treated with screw fixation, type V fractures usually lead to an unsuccessful clinical result. A central tarsal replacement composed of a titanium alloy was developed by our investigation team to treat type V fractures. The implant was used to successfully treat a greyhound and to allow it to return to racing. Continual development of this new surgical procedure hopefully will give the veterinarian predictable and reliable clinical results and return injured greyhounds to active racing.     

Caffeine--the potential for its abuse in the racing greyhound

The effects of caffeine and its availability as a drug or constituent of beverages is described. The literature concerning the effect of caffeine in greyhounds is reviewed and deductions are made and tested by experimental work. Thus conclusions are drawn as to how caffeine affects greyhound racing carried out under the National Greyhound Racing Club (NGRC) rules.     

Haematology and serum biochemistry in the racing greyhound following intraperitoneal povidone-iodine

Povidone-iodine caused peritonitis with neutrophilic leukocytosis and a minimal left shift at the dosage rate of 3.5 ml/kg body weight. A dosage rate of 2 ml/kg only caused slight neutrophilic leukocytosis. There was a significant increase in the levels of creatinine (p=0.049) and BUN (p=0.020) in dogs that received the higher dose rate. Two dogs died from povidone-iodine toxicity with a marked increase in ALT, AP, SDH and conjugated bilirubin. It is concluded that povidone-iodine is unsafe for use in the peritoneal cavity of dogs.     

Sprain of the short radial collateral ligament in a racing greyhound

Severe carpal lameness in a racing greyhound due to a sprain of the straight part of the short radial collateral ligament is described. The dog subsequently developed an enthesiopathy at the origin of the ligament. Treatment was by kennel rest and the dog returned to successful racing.     

Lateral ligamentous injury to the carpus of a racing greyhound

The lateral collateral ligament of the ulna and the dorsolateral ligaments of the radiocarpal joint of a racing Greyhound were ruptured, resulting in instability of the carpus when the joint was flexed. This report describes a technique for making a ligament prosthesis, using the ulnaris lateralis tendon. Although the dog did not return to racing, the carpus was stable enough for general activity.     

Successful derotation of a splenic torsion in a racing greyhound

A two-year-old male racing greyhound was presented to the Sydney University Veterinary Hospital with a six-week history of intermittent gastric dilatation. Abdominal radiography and ultrasonography were suggestive of splenic torsion without gastric dilatation. Exploratory ceoliotomy confirmed a 540° clockwise rotation of the spleen. Derotation of the spleen was performed and thrombosis was not present in the splenic vessels. Epinephrine was injected into the splenic parenchyma to aid in splenic contraction. The spleen was left in situ. The greyhound made an uneventful recovery and has won several races in the 10-month follow-up period without further problems.     

Histological analysis of a central tarsal implant in a racing greyhound

The hock of a greyhound containing a titanium alloy central tarsal replacement was examined histologically. The animal had raced competitively 43 times before retirement. The examination showed that the adaptation and encapsulation of the implant by the surrounding bones, together with the excellent purchase of the screw into the fourth tarsal bone, had maintained the implant in excellent position during vigorous load-bearing. There was no histopathological evidence to suggest that the fixation of the implant was failing. The results provide evidence for the value of titanium alloy implants as a central tarsal replacement in greyhounds with type V fractures, and as a feasible alternative to euthanasia.     

Cranial cruciate ligament pathophysiology in dogs with cruciate disease: a review

Cruciate disease is a common cause of chronic lameness in dogs. Midsubstance rupture of the cranial cruciate ligament (CCL) arises from progressive pathological failure, often under conditions of normal loading in adult dogs with CCL instability. A high risk of rupture is associated with inflammation of the synovium and adaptive or degenerative changes in the cells and matrix of the CCL. In contrast, CCL rupture in puppies is usually associated with traumatic injury and avulsion of the CCL from its sites of attachment.     

Cranial cruciate ligament rupture in the dog—a retrospective study comparing surgical techniques

SUMMARY Three surgical techniques, grouped as intra-articular techniques, extra-capsular techniques and fibular head transposition, were used for repair of the cranial cruciate ligament (CCL)-deficient stifle in 113 dogs over a 4 year 4 month period. The clinical outcome of the techniques were compared using information provided by the owners and physical examination. Regardless of surgical technique, 85.7 to 91.0% of dogs showed clinical improvement after surgery. However, less than 50% of dogs became clinically sound on the operated leg and 9.0 to 14.3% of dogs remained persistently lame on the operated leg. No statistical association was found between result after surgery and age, body weight, sex, duration of injury before surgery, association with injury, tibial plateau angle, degree of radiographic osteoarthritis before surgery or the presence of concurrent medial meniscal injury. On physical examination, extra-capsular techniques appeared superior to the fibular head transposition in terms of joint stability and limb function. Concurrent medial meniscal injury necessitating meniscectomy existed in 48.0% of cases. Twenty-two percent of dogs ruptured their contralateral CCL at an average of 14 months after the first.     

Cranial cruciate ligament injury in the dog: pathophysiology, diagnosis and treatment

Cranial cruciate ligament (CCL) disease in the dog is a multifactorial complex problem that requires a thorough understanding of the biomechanics of the stifle joint to be understood. Successful treatment of rupture of the CCL should be based on managing underlying anatomical and conformational abnormalities rather than attempting to eliminate the tibial cranial drawer sign. The cranial and caudal cruciate ligaments, the patella ligament and quadriceps mechanism, the medial and lateral collateral ligaments, the medial and lateral menisci and the joint capsule provide stability of the joint and load-sharing. The function of the stifle is also significantly influenced by the musculature of the pelvic limb. An active model of biomechanics of the stifle has been described that incorporates not only the ligamentous structures of the stifle but also the forces created by weight-bearing and the musculature of the pelvic limb. This model recognises a force called cranial tibial thrust, which occurs during weight-bearing, and causes compression of the femoral condyles against the tibial plateau. In middle-aged, large-breed dogs, forces acting on the CCL together with conformation-related mild hyperextension of the stifle and slightly increased tibial plateau slopes are suspected to cause progressive degeneration of the ligament. Palpation of craniolateral stifle laxity has become pathognomonic for CCL rupture; however, chronic periarticular fibrosis, a partial CCL rupture, and a tense patient, may make evaluation of instability of the stifle difficult. Surgical treatment is broadly separated into three groups: intracapsular, extracapsular, and tibial osteotomy techniques. Tibial osteotomy techniques do not serve to provide stability of the stifle but rather alter the geometry of the joint to eliminate cranial tibial thrust such that functional joint stability is achieved during weight-bearing. Visualisation of both menisci is a critical aspect of CCL surgery, irrespective of the technique being performed. Regardless of the surgical technique employed, approximately 85% of dogs show clinical improvement. However, many of these dogs will demonstrate intermittent pain or lameness. Post-operative management is an integral part of the treatment of CCL rupture, and significant benefits in limb function occur when formalised post-operative physiotherapy is performed.