Patellar groove replacement in patellar luxation with severe femoro-patellar osteoarthritis.

OBJECTIVE: To report a novel method of treating femoro-patellar instability in association with severe femoro-patellar osteoarthritis, by substituting the femoral trochlear with a patellar groove replacement prosthesis. STUDY DESIGN: Retrospective case series. METHODS: Preoperative lameness was scored from 0-4, and radiographic studies including standard positions for patellar luxation were obtained for evidence of malalignment and femoro-patellar osteoarthritis. Cases with or without previous surgeries were included. The size of trochlear implant was determined by transparent templates and confirmed intra-operatively with trials. Radiographic images, together with clinical examinations, were reviewed immediately and at three months postoperatively and at longer term when available. RESULTS: Thirty-five cases of patellar luxation ranging from grades II to IV were included. Eleven of these cases had prior surgical interventions which failed to stabilize the patella. Fourteen dogs required additional surgical procedures in conjunction with patellar groove replacement. Complications occurred in six patients, of which three required revision. Complete resolution of subjectively-assessed lameness was evident in 24/35 cases by the third month and in another seven of 35 patients on the longer term re-evaluations. CLINICAL SIGNIFICANCE: Use of a patellar groove replacement prosthesis has the potential to decrease the lameness associated with severe femoro-patellar arthritis, to improve patellar stability, and to correct the alignment of the extensor mechanism.

Distraction-stabilisation of two adjacent intervertebral spaces in a Dalmatian dog with caudal cervical spondylomyelopathy.

A 4-year-old, 40-kg, male, entire Dalmatian was presented for evaluation of chronic neck pain and pelvic limb ataxia. Myelography revealed ventrodorsal (hourglass) extradural compression over the intervertebral space between the 5th and 6th cervical vertebra and ventral extradural compression between the 6th and 7th cervical vertebra. Cranial compression disappeared and caudal compression markedly diminished after performing cervical traction. MRI scan confirmed protrusion of intervertebral discs and spinal cord compression in previously mentioned intervertebral spaces. Surgical distraction-stabilization of both intervertebral spaces was performed using threaded pins and polymethylmethacrylate. The convalescence from surgery was uneventful and the dog was walking without any signs of paresis until 5 months after surgery when radiography revealed implants loosening. The dog recovered fully of the implant removal and remained asymptomatic for more than 30 months.

The cranial instrument port in arthroscopy of the canine shoulder joint.

We describe the creation of a cranial instrument portal for shoulder joint arthroscopy in the dog using a target device that has been successfully employed for the caudal access. We compared the method with a conventional triangulation technique. The shoulder joints of 60 dog cadavers were investigated by arthroscopy and the two methods were compared on the basis of pre-defined parameters of outcome. Time, the number of trials, success, damage to cartilage and the accessibility of intra-articular structures were assessed. The anatomical localisation of the working cannula in muscles was also documented. In general, the new method permitted more successful insertion of the working cannula. This was achieved in a shorter period of time and was associated with fewer insertion attempts as well as less damage to joint cartilage. Intra-articular structures could be readily approached through the working cannula with both methods. Predetermined, clinically relevant points were comparatively more accessible with the new technique. Independent of the method, in only a few cases, the working cannula perforated neither muscles nor tendons when accessing the joint. It may be concluded that the new method using a target device is simpler and safer and offers a standardised technique to establish a cranial instrument port.

Measurement of the tibial plateau angle in cats with and without cranial cruciate ligament rupture.

The objective of the present study was to determine the tibial plateau angle (TPA) in cats without stifle pathology and to compare it with cats suffering from an isolated cranial cruciate ligament rupture. Mediolateral radiographs of the stifle were taken and the tibial plateau angle was measured based on the method previously described by Slocum and Devine (1983) for dogs. Three observers with different levels of experience evaluated the radiographs of all of the cats in this study. The mean tibial plateau angle measured by all three observers in the cats with a rupture of the cranial cruciate ligament (CCL) was 3.1 degrees greater than in cats without stifle pathology. Neither gender, age, body weight nor degenerative joint disease had an influence on measurement results. The authors found an inter-observer variability of +/- 5.3 degrees . Hence it can be concluded that cats with cranial cruciate ligament rupture have a greater TPA, and this at least lends some credence to the possibility of higher TPA being a predisposing factor for cruciate injury in this species.

Signalment differences in bone mineral content and bone mineral density in canine appendicular bones. A cadaveric study.

The objective was to determine signalment-related differences in bone mineral content (BMC) and bone mineral density (BMD) in dogs. Unilateral appendicular bones were harvested from 62 canine cadavers. Mid-diaphyseal regions of interest (ROIs) were scanned using a Hologic DXA device Braincon, Vienna, Austria). BMC and BMD were calculated within this region. Middle-aged dogs (3-10 years) revealed the highest BMC and BMD levels. Mean BMC and BMD were higher in males compared to females. Furthermore, body-weight of the male dogs was significantly higher compared to the females (P < 0.0001). Body weight and bone length were significantly associated with BMC and BMD (P < or = 0.023) in all bones but the radius. These data suggest that BMC and BMD appear to be highest in male large-breed dogs with a body weight greater than 30 kg. These results may help determine risk factors in fracture development and healing.

Effects of radial shockwave therapy on the limb function of dogs with hip osteoarthritis.

The objective of this study was to evaluate the effects of extracorporeal radial shock wave therapy on the hindlimb function of dogs suffering from hip osteoarthritis. Twenty-four client-owned dogs with hip osteoarthritis were investigated; 18 of them received radial shockwave therapy and six were left untreated as controls. Force plate analysis on a treadmill was used to assess the dogs' hindlimb function before treatment and four weeks after the last treatment, and the treated dogs were re-evaluated three and six months after the treatment. The parameters chosen for evaluation were peak vertical force and vertical impulse, and the calculated symmetry indices. In the treated dogs, differences between the ground reaction forces exerted by the right and left hindlegs disappeared four weeks after the treatment, whereas in the control dogs only the peak vertical force distribution changed significantly. The significant improvement in the treated dogs was confirmed by changes in the symmetry indices. Significant improvements in vertical impulse and peak vertical force were observed three months after the treatment.

Traumatic triceps tendon avulsion in a cat.

Traumatic avulsion of the triceps tendon was diagnosed in a 15-month-old, male, neutered European shorthair cat. Diagnosis was established clinically by palpation of a transverse groove proximal to the olecranon and by radiography. The avulsed end of the tendon was surgically reapposed using a modified three-loop pulley suture and horizontal mattress sutures. Postoperatively, elbow flexion was limited for three weeks with the aid of a spica splint and by exercise restriction for six weeks. The cat showed no lameness after bandage removal up to the time of writing (seven months). Although rare, triceps tendon injuries can occur after a blunt trauma and should be included in the differential diagnosis of foreleg lameness in the cat. The modified three-loop pulley suture in combination with subsequent immobilisation of the limb with a splinted bandage resulted in a successful outcome in this cat with a triceps tendon avulsion.

Traumatic avulsion fracture of the lesser trochanter in a dog.

A 15-month-old 25 kg female spayed American Staffordshire Terrier was examined to determine the cause of a six month period of lameness of the left pelvic limb. Signs of severe pain were evident on hyperextension and simultaneous internal rotation or abduction of the left hip joint; crepitus or instabiltiy was not detected. The diagnosis of avulsion fracture of the lesser trochanter was based on radiographs, computed tomography (CT) and magnetic resonance imaging (MRI), supported by initial findings such as lameness and hip joint pain in extension. The dog was treated with strict confinement for eight weeks followed by a gradual increase in activity; non-steroidal anti-inflammatory drugs were given for one month. Three months later, the dog was clinically sound and unrestricted activity was resumed. Soundness was confirmed on follow-up 18 months after injury. CT and especially MRI were powerful diagnostic tools to identify chronic iliopsoas strains with an avulsion fracture of the lesser trochanter. Complete recovery ensued following conservative treatment only, despite the proximal diplacement of an avulsed segment of the lesser trochanter. Thus, traumatic injury to the iliopsoas muscle and to the lesser trochanter should be included as differential diagnosis in cases of hind leg lameness.

Iliopsoas abscess with iliac and femoral vein thrombosis in an adult Siberian husky.

A nine-year-old, male Siberian husky was presented with fever, decreased appetite and activity, non-weightbearing lameness, and oedematous swelling of the right inguinal and preputial area and the right hindlimb. An abscess within the right iliopsoas muscle, with severe thrombosis of the iliac and femoral vein, was diagnosed by haematology and diagnostic imaging. The abscess and adjoining lymph node were removed surgically through a median coellotomy. The isolated pathogen was Staphylococcus intermedius. Clinical signs resolved completely after surgery. Antimicrobial therapy was continued for four weeks. Within the follow-up period of six months, no recurrence of the clinical signs was detected.

Long-term outcome of medical and surgical treatment of hiatal hernias in dogs and cats: 27 cases (1978-1996).

OBJECTIVE: To determine long-term outcome of medical and surgical treatment of hiatal hernia (HH) in dogs and cats. DESIGN: Retrospective case series. ANIMALS: 22 dogs and 5 cats. PROCEDURE: Medical records of dogs and cats with HH were reviewed. Outcomes of treatment were obtained from reexamination or owner questionnaires. RESULTS: The most common breeds affected were English Bulldog and domestic shorthair cat. Mean age of all dogs and cats was 4 years. Hiatal hernia was diagnosed by use of contrast radiography of the esophagus (n = 19), fluoroscopy (7), or esophagoscopy (1). Eight of 15 dogs and cats treated medically for 30 days had complete resolution of signs. Of the 7 in this group that did not respond, 1 died on the 10th day of medical treatment and the remaining 6 were treated surgically. Eight of 10 dogs that underwent hiatal plication, esophagopexy, and gastropexy responded favorably. Four of 7 dogs that underwent fundoplication did well. However, 3 of these dogs did not have clinical signs. Fundoplication was successful in only 1 of 4 dogs with clinical signs. CLINICAL IMPLICATIONS: Dogs and cats with clinical signs of reflux esophagitis associated with HH should undergo conservative treatment for 30 days. Most will be managed successfully by use of drugs, dietary alterations, or both. Those that do not respond to conservative treatment will likely require surgery. The best prognosis after, surgery appears to be associated with the esopagopexy technique.

Short-term hemodynamic evaluation of circumferential mitral annuloplasty for correction of mitral valve regurgitation in dogs.

OBJECTIVE: To determine the short-term hemodynamic effects associated with circumferential mitral annuloplasty (CMA) in dogs with mitral regurgitation. STUDY DESIGN: Prospective experimental study. Animals-Seven healthy adult mongrel dogs. METHODS: Mitral regurgitation was surgically induced, and annular dilation occurred. Echocardiography and cardiac catheterization were used to determine forward ejection fraction (FEF), regurgitant fraction (RF), pulmonary capillary wedge pressure (PCWP), and annular diameter before and immediately after CMA in five dogs. FEF and RF were also evaluated 7 days after annuloplasty. RESULTS: Mean annular diameter and PCWP were significantly reduced immediately after CMA. Significant increases in FEF of 19% and 22% were shown immediately and 7 days after CMA. Significant reductions in RF of 19% and 22% were also shown immediately and 7 days after annuloplasty. CONCLUSIONS: Sustained hemodynamic benefits and a reduction in annular diameter were achieved by CMA in a canine model of mitral regurgitation. CLINICAL IMPLICATIONS: CMA may be a suitable treatment for heart failure because of mitral regurgitation when early signs of cardiovascular decompensation persist despite appropriate medical management.

Determination of proximal femoral epiphyseal depth for repair of physeal fractures in immature dogs.

OBJECTIVE: To determine the depth that implants may be safely placed for repair of proximal femoral physeal fractures. STUDY DESIGN: Relationships were determined between the depth of the proximal femoral epiphysis (PFE) and the contralateral PFE, and the PFE and pubic bone width. ANIMALS OR SAMPLE POPULATION: 20 immature dog cadavers. METHODS: Actual PFE depths were determined at the center of the physeal surface and at four other eccentric points. The contralateral intact PFE depth and the width of the cranial aspect of the public bone were measured from radiographs. RESULTS: Mean ratios of actual central PFE depth to radiographically measured (1) contralateral PFE depth and (2) pubic bone width were 1.04:1, and 1.09:1, and ratios of actual eccentric PFE depths were 0.89:1 and 0.93:1. Body weight was not useful in estimating depth of the PFE. CONCLUSIONS: For the central epiphysis, pins may safely be placed a distance equal to 75% to 80% of the contralateral intact PFE depth or pubic bone width, measured from a ventrodorsal radiograph, with minimal risk of penetration through the articular surface. Pins placed eccentrically may be safely driven a depth equal to 65% of the radiographically measured contralateral intact PFE depth or pubic bone width. CLINICAL RELEVANCE: Estimating the safe depth of implant placement into the PFE avoids penetration of the articular surface.

Determination of safe depth of pin penetration for repair of distal femoral physeal fractures in immature dogs: a comparison of normograde and retrograde pin placement.

OBJECTIVE: The purpose of this study was to determine the depth that implants may be safely placed into the distal femoral epiphysis (DFE) for the repair of distal femoral physeal fractures. STUDY DESIGN: The depth of the DFE was related to the radiographic thickness of the patella in this experimental study. ANIMALS OR SAMPLE POPULATION: Twenty immature canine cadavers. METHODS: Patella thicknesses were measured from lateral radiographs. Actual DFE depths were determined for pins driven in normograde fashion and for pins driven retrograde from the central depression between the metaphyseal pegs and from the cranial pegs. The association of DFE depth and patella thickness was evaluated using linear regression analysis. Using 95% confidence intervals, rules for estimating the safe depth of implant placement into the DFE were determined. RESULTS: DFE depth had significant correlation with patella thickness for pins placed in retrograde fashion from the central depression between the metaphyseal pegs (r2 = .83) and from the cranial pegs (r2 = .82) and for pins placed in normograde fashion (r2 = .65). CONCLUSIONS: Based on 95% confidence intervals, pins placed in retrograde fashion from the central depression between the metaphyseal pegs may be safely driven into the DFE a distance equal to 140% of patella thickness. Pins placed from the cranial metaphyseal pegs may be driven to a depth equal to 80% of patella thickness, and pins placed in normograde fashion may be driven to a depth equal to 30% of patella thickness. CLINICAL RELEVANCE: Measurement of patella thickness assists the surgeon in determining the approximate depth that pins may be driven into the DFE without penetrating the articular surface of the stifle joint.