Intramuscular mast cell tumors in 7 dogs.

Mast cell tumors (MCTs) are commonly encountered in dogs and have been reported in cutaneous, conjunctival, oral mucosal, and gastrointestinal locations, but not in an intramuscular location. Medical records at 2 referral centers in the UK were examined to find cases of MCTs in this location. Seven dogs were identified as having an intramuscular MCT by a combination of fine-needle aspirate cytology and computed tomography or ultrasound. None of the dogs had evidence of local lymph node metastasis. Six dogs had no evidence of distant metastasis and surgery was carried out as the primary treatment option. Three of those dogs also had adjunctive chemotherapy due to a high Ki67 value or high mitotic index. All 6 dogs that had had surgery were alive at follow-up with a minimum elapsed time of 7 months. One dog had a course of chemotherapy due to the location, size, and evidence of biological activity of the tumor and died 23 days afterwards. The prognosis of intramuscular mast cell tumors appears to be favorable in most cases.

Tumeurs à mastocytes intramusculaires chez sept chiens. Les tumeurs à mastocytes (MCT) sont couramment observées chez les chiens et elles sont signalées à des emplacements cutanés, conjonctivaux, gastrointestinaux et dans les muqueuses orales, mais non dans des régions intramusculaires. Les dossiers médicaux de deux centres spécialisés du Royaume-Uni ont été examinés afin de trouver des cas de MCT à cet endroit. Sept chiens ont été identifiés comme ayant un MCT intramusculaire en utilisant une combinaison de cytologie par aspiration à l'aiguille fine et de tomodensitométrie ou d'échographie. Aucun des chiens ne présentait des signes de métastase des ganglions lymphatiques locaux. Six chiens ne manifestaient aucun signe de métastase distante et la chirurgie a été réalisée comme option de traitement primaire. Trois de ces chiens ont aussi subi une chimiothérapie d'appoint en raison d'une valeur élevée de Ki67 ou d'un indice mitotique élevé. Les six chiens qui avaient subi la chirurgie étaient vivants au suivi avec un délai écoulé de 7 mois. Un chien a subi un traitement de chimiothérapie en raison de l'emplacement, de la taille et de signes d'activité biologique de la tumeur et est mort 23 jours plus tard. Le pronostic de tumeurs à mastocytes intramusculaires semble être favorable dans la plupart des cas.(Traduit par Isabelle Vallières).

Sacroiliac luxation in the cat: defining a safe corridor in the dorsoventral plane for screw insertion in lag fashion.

OBJECTIVE: To define a safe corridor in the dorsoventral plane within the feline sacral body for placement of screws inserted in lag fashion for repair of sacroiliac luxation. STUDY DESIGN: Anatomic study. SAMPLE POPULATION: Frozen cadaveric feline sacra. METHODS: Feline sacra (n=20) were used to perform a radiographic study to define a safe corridor to a depth of 66% of the sacral body width. Two drill start points (A and B) were evaluated. Dorsal exit from the safe corridor was considered unacceptable. RESULTS: Forty safe corridors were measured. The mean articular surface was 100+/-6.4 degrees from horizontal. Mean maximum, optimum, and minimum safe corridor drill angles from drill point A were 107+/-6.8 degrees , 97+/-6.9 degrees , and 87+/-7.2 degrees , respectively, from the articular surface. Mean maximum, optimum, and minimum angles from drill point B were 109+/-7.2 degrees , 99+/-7.1 degrees , and 89.5+/-7.2 degrees , respectively. Point B increased the risk of ventral exit from the sacral body. CONCLUSIONS: Point A and a drill angle of 90+/-4 degrees for drilling of the feline sacral body is recommended. This margin for error risks ventral exit from the body in 23/40 (58%) of the sacra in this study. Reduction of the margin for error to +/-2 degrees would reduce the risk of ventral exit to 14/40 (35%) of the sacra in this study. CLINICAL RELEVANCE: Drilling at 90 degrees to the feline sacral articular surface is recommended. Findings from this study present a strong case for use of angled drill guides.

Dorso-medial ante-brachiocarpal luxation with radio-ulna luxation in a domestic shorthair.

An 8-year-old domestic shorthair was admitted with non-weight bearing left forelimb lameness. Examination and radiographs revealed dorso-medial ante-brachiocarpal luxation with palmar luxation of the distal radio-ulnar joint. Primary repair was performed and stabilised using an arthrodesis wire and type Ia Kirschner-Ehmer (K-E) external skeletal fixator (ESF). The cat regained excellent pain-free limb function by 14 weeks with only minor reduction in range of movement. This is the first case report of a cat with distal radio-ulnar joint luxation associated with ante-brachiocarpal luxation. Primary repair of carpal luxation in the cat should be considered before arthrodesis.

Canine sacroiliac luxation: anatomic study of dorsoventral articular surface angulation and safe corridor for placement of screws used for lag fixation.

OBJECTIVE: To define a safe corridor in the dorsoventral plane to facilitate placement of screws inserted in lag fashion within the sacral body for fixation of sacroiliac fracture-luxation injuries in dogs. STUDY DESIGN: Anatomic study. SAMPLE POPULATION: Cadaveric canine sacra. METHODS: Canine sacra (n=45) were used for a radiographic study to define a safe corridor in the dorsoventral plane for placement of screws inserted in lag fashion for fixation of sacroiliac luxation in the dog. The defined safe corridor allowed drilling to a depth of 65% of the sacral width to ensure screw purchase of > or =60%. Effects of positioning and measurement techniques were evaluated. RESULTS: Eighty-seven safe corridors were measured. The mean articular surface was 100+/-4.52 degrees from horizontal. Mean maximum, optimum, and minimum safe corridor drill angles were 111+/- 4.57 degrees, 100+/-4.70 degrees, and 89+/-5.17 degrees, respectively, from the articular surface. Predicted surgeon error of +/-4 degrees was used to define the safe corridor for use clinically. CONCLUSIONS: In 91% of sacra, a drill angle of 100+/-4 degrees would remain ventral to the vertebral canal. Twelve sacra (14%) were at risk of penetration of the pelvic canal. A drill angle of 97+/-4 degrees avoids penetration of the vertebral canal in all sacra measured but risks ventral exit from the body in 30% of sacra studied. CLINICAL RELEVANCE: A drill angle of 97 degrees from the articular surface is recommended for insertion of screws for lag fixation of canine sacroiliac luxation.