Diagnostic performance of CUBE MRI sequences of the knee compared with conventional MRI.

AIM: To evaluate the efficacy and efficiency of three-dimensional (3D) fast spin-echo (FSE) with variable flip angle ("CUBE") magnetic resonance imaging (MRI) in knee imaging as compared with conventional MRI. MATERIALS AND METHODS: Twenty-nine patients (single knee) with joint injuries of varying degrees were enrolled in this study between January, 2011 and December, 2011. All patients underwent conventional MRI and a fat-suppressed CUBE MRI sequence. All patients subsequently underwent knee arthroscopic surgery performed by an experienced orthopaedic surgeon within 2 weeks after the MRI examinations. With standard reference provided by arthroscopic results, the sensitivity, specificity, and accuracy of both the CUBE and conventional MRI techniques were calculated for detecting cartilage lesions, meniscus tears, and anterior cruciate ligament injuries, respectively. A chi-square test was used for statistical analysis with a level of significance of p < 0.05. RESULTS: For the evaluation of articular cartilage lesions, the CUBE sequence had higher sensitivity (70.9% versus 50.6%, p < 0.01), higher specificity (72.6% versus 58.9%, p < 0.05), and higher accuracy (71.8% versus 55.2%, p = 0.001) than conventional MRI. For the evaluation of meniscus tears, CUBE and conventional MRI had similar sensitivity, specificity, and accuracy (p = 0.20-0.55). Similarly, there was no significant difference in sensitivity, specificity, or accuracy between CUBE imaging and conventional imaging in the detection of anterior cruciate ligament injuries (p = 0.13-0.65). CONCLUSION: CUBE MRI has similar or superior sensitivity, specificity, and accuracy to a conventional imaging protocol in the comprehensive evaluation of knee joint injuries.

Minimally displaced tibial tuberosity avulsion fracture in nine skeletally immature large breed dogs.

OBJECTIVE: The objective of this study was to describe the clinical and radiographic features, as well as the treatment and outcome of minimally displaced tibial-tuberosity-avulsion-fractures (MDTTAF). MATERIALS AND METHODS: Signalment, history, diagnostics, therapy, and outcome were recorded. Follow-up was documented as re-examination, radiographic assessment or telephone conversation. RESULTS: Nine large breed dogs that were presented with lameness originating from the proximal tibia were included. All showed signs of pain when pressure was applied to the tibial tuberosity. There was no stifle instability or intra-articular disease. The main feature on mediolateral radiographs was a widened tibial-tuberosity-physis with reactive new bone and loss of edge definition of the epiphyseal and metaphyseal margins. Non-surgical treatment was chosen in eight dogs, and surgery in one dog. Radiographic follow-up showed progressive closure of the tibial-tuberosity-physis and healing. Clinical signs resolved at a median of 28 days (range: 14-120). DISCUSSION: Minimally displaced tibial-tuberosity-avulsion-fractures should be a differential diagnosis in skeletally immature large breed dogs older than nine months of age with signs of subtle pelvic-limb lameness, and signs of proximal tibial pain, but no evidence of stifle joint disease. Thorough clinical examination and critical review of bilateral radiographs are important to diagnose MDTTAF. The outcome in these cases suggests that the prognosis for MDTTAF is excellent. Age and size of the affected dogs in this study differ from an earlier publication that illustrated more severely displaced tibial tuberosity avulsion fractures, occurring mainly in terriers around five months of age.

Alveolar mucosal approach to the canine nasal cavity.

A nine-year-old, intact female Afghan hound was presented for evaluation of an intermittent, mucopurulent, unilateral nasal discharge with a three-year duration. Radiographs showed the ipsilateral canine tooth within the rostral nasal cavity. The tooth was removed through an alveolar mucosal rhinotomy. There has been no recurrence of the nasal discharge or complications associated with the surgical procedure during the 20-month follow-up period.

Arthroscopic removal and curettage of osteochondrosis lesions on the lateral and medial trochlear ridges of the talus in two dogs.

Osteochondrosis lesions in the tibiotarsal joint were treated arthroscopically in two dogs. One dog had unilateral osteochondrosis of the dorsal aspect of the lateral trochlear ridge of the talus. The second dog had bilateral osteochondrosis of the plantar aspect of the medial trochlear ridge of the talus. Removal of all osteochondral fragments (i.e., joint mice) and debridement and curettage of the remaining talar defects were accomplished arthroscopically. Both dogs had excellent short-term outcomes.

Effect of ascorbate and two different media on canine chondrocytes in three-dimensional culture.

The objective of this study was to determine the effects of ascorbate and two different culture media on cell morphology and extracellular matrix formation of canine chondrocytes grown in a three-dimensional (3-D) culture system. Articular cartilage harvested from the humeral head of three adult canine cadavers was used to obtain chondrocytes for primary culture. Subcultured chondrocytes were seeded in a 3-D medium of RPMI-1640 (R), RPMI-1640 with 50 microg/mL ascorbate (RA), Ham's F-12 (F), or Ham's F-12 with 50 microg/mL ascorbate (FA) in agarose. Samples were harvested at 5, 10, 15, and 20 days of 3-D culture and analyzed for histologic appearance and proteoglycan staining, electron microscopic appearance, dimethylmethylene blue assay for glycosaminoglycan (GAG) content, and immunohistochemical staining for collagen type II production. Chondrocytes in all four groups maintained appropriate morphology and produced matrix over the entire study period. Chondrocytes from groups R and RA produced more GAG and collagen type II than did those from groups F and FA on days 10 (P = .00791) and 15 (P = .0173). Chondrocytes from group RA produced more GAG on days 5 (P = .0154) and 20 (P = .0044) than did those in groups R, F, and FA. With respect to matrix production, RPMI-1640 is superior to Ham's F-12 for 3-D culture of canine chondrocytes. The addition of ascorbate at 50 microg/mL to RPMI-1640 did have a positive effect on the production of GAG but had minimal effect on type II collagen production. Determining the most ideal in vitro microenvironment for canine chondrocytes grown in a 3-D culture system has important implications to the in vivo application of this technique.