Andrew P. Moores

Computed tomography versus arthroscopy for detection of canine elbow dysplasia lesions.

OBJECTIVE To describe associations between computed tomography (CT) and arthroscopy in dogs with elbow dysplasia lesions. STUDY DESIGN Retrospective clinical study. SAMPLE POPULATION Canine elbows (n=101) investigated by CT and arthroscopy. METHODS CT scans were reviewed for 10 predetermined CT signs and graded for osteophyte size. Surgical reports were reviewed for specific disease features and cartilage erosion grades. Associations between variables were investigated with multivariate logistic regression and correlation between osteophyte size and cartilage erosion with Spearmans rank order correlation. RESULTS Medial coronoid process (MCP) fragment on CT was significantly associated with the arthroscopic identification of a displaced MCP fragment, cartilage erosion affecting the MCP, and cartilage erosion affecting the humeral condyle. Irregular radial incisure of the ulna on CT was significantly associated with the arthroscopic identification of cartilage erosion affecting the MCP. Osteophytes on CT were significantly associated with an abnormal arthroscopic examination. There was a moderately significant correlation between CT osteophyte grade and cartilage erosion grades for areas of the medial joint compartment (r(s)=0.44-0.48). CONCLUSION Some CT signs are significantly associated with arthroscopic features of elbow dysplasia lesions in dogs; however, other CT signs were not associated with arthroscopic findings, and CT and arthroscopy can provide contradictory information. Osteophyte size is moderately correlated with cartilage erosion of the medial joint compartment. CLINICAL RELEVANCE CT can provide valuable information for the investigation of dogs with elbow dysplasia, but the absence of CT signs (or the absence of arthroscopic abnormalities) does not rule out elbow lesions.

Spectrum of computed tomographic findings in 58 canine elbows with fragmentation of the medial coronoid process.

OBJECTIVE To describe in detail the computed tomographic findings in elbows of dogs with fragmentation of the medial coronoid process of the ulna. METHODS Retrospective review of computed tomographic images of 58 elbows that had displaced medial coronoid process fragment(s), non-displaced medial coronoid process fragment or a stable fissure in the articular cartilage of the medial coronoid process at arthroscopy. RESULTS Bone fragments were observed in 85 per cent elbows with a displaced fragment at arthroscopy, in 18 per cent elbows with a non-displaced fragment and in 29 per cent elbows with a stable fissure. Fissures in the subchondral bone were observed in computed tomographic images of 43 per cent elbows that had a stable fissure at arthroscopy. Abnormal shape, sclerosis and lucency affecting the medial coronoid process, subchondral sclerosis of the ulna and humerus, irregular radial incisure of the ulna and periarticular osteophytes were observed in a similar proportion in dogs regardless of the arthroscopic findings. Kissing lesions affecting the medial aspect of the humeral condyle were mainly associated with displaced fragments. Signs of joint incongruity were observed in dorsal and sagittal reconstructed computed tomographic images in 24 per cent elbows. CLINICAL SIGNIFICANCE A wide range of abnormalities may be observed in computed tomographic images of dogs with fragmented medial coronoid process. Computed tomographic is moderately sensitive for detection of fragments.

Epoxy putty external skeletal fixation for fractures of the four main metacarpal and metatarsal bones in cats and dogs

The objective of this retrospective study was to report the clinical use, advantages, disadvantages, complications and outcome of an epoxy putty external skeletal fixator (EPESF) used for the repair of fractures of all four main metatarsal or metacarpal bones in a single limb in 11 dogs and 11 cats. The aim of this technique was to achieve satisfactory alignment of the proximal and distal joints and the digits, rather than anatomical reconstruction of the metacarpal/metatarsal bones themselves. All of the cases achieved fracture union and they all recovered fully without any residual lameness.

Tibial tuberosity avulsion fracture in dogs: a review of 59 dogs.

OBJECTIVES To evaluate the high incidence of tibial tuberosity avulsion fracture diagnosed in skeletally immature Staffordshire bull terriers presenting to a UK animal welfare charity hospital. METHODS A retrospective review of tibial tuberosity avulsion fractures treated by the hospital between 2002 and 2007. RESULTS Sixty-five tibial tuberosity avulsion fractures were recorded in 59 dogs. Fifty-one tibial tuberosity avulsion fracture-affected dogs (86 per cent) were Staffordshire bull terriers. Dogs sustaining tibial tuberosity avulsion fractures had median and mean ages of five and 4.9 months, respectively (range three to 10 months). Where recorded, injury was associated with a short fall or jump (typically 3 to 4 feet) in 29 of 50 dogs. Three fracture patterns were recorded: 37 stifles sustained isolated tibial tuberosity avulsion fracture; 15 stifles sustained tibial tuberosity avulsion fracture accompanied by separation of the proximal tibial epiphysis; in 13 stifles epiphyseal separation extended to produce Salter-Harris type II fracture of the caudal tibial metaphysis. On analysis of the hospital database, tibial tuberosity avulsion fracture was a reason for presentation in 51 (3.3 per cent) of 1536 Staffordshire bull terriers, but only five (0.18 per cent) of 2815 other breed dogs, registered under the age of 12 months during the study period (P<0.001). CLINICAL SIGNIFICANCE Staffordshire bull terriers commonly present with tibial tuberosity avulsion fracture, with or without concurrent separation of the proximal tibial epiphysis, to this urban charity hospital.

In Vitro Comparison of Mechanical and Degradation Properties of Equivalent Absorbable Suture Materials from Two Different Manufacturers

OBJECTIVE To compare the mechanical, knotting, and absorption properties of 3 synthetic absorbable suture materials (polyglactin 910, polydioxanone, poliglecaprone 25) from 2 different manufacturers (Huaiyin Medical Instruments Co. Ltd. and Ethicon Inc.). SAMPLE POPULATION Suture material samples from the same manufacturing lot for each suture type and manufacturer. METHODS Part 1: 10 samples of each suture were incubated in bovine serum and tested for ultimate load and stiffness at days 0, 1, 7, 14, 21, and 28. Part 2: 10 knotted samples were similarly evaluated, without incubation. RESULTS Huaiyin polydioxanone had a greater (P<.001) ultimate load on days 0, 1, and 7; and a consistently greater stiffness for the duration of the study, compared with the Ethicon polydioxanone. Ethicon poliglecaprone 25 had a greater ultimate load on days 0, 1, 7 (P<.001); on day 21 Huaiyin had a greater ultimate load. Ethicon poliglecaprone had greater stiffness on days 0, 1, 7 (P<.001). Ethicon polyglactin 910 had a greater (P<.001) ultimate load at all times and a greater stiffness (P<.001) at days 0, 1, 7, and 14 compared with Huaiyin polyglactin 910. Huaiyin polydioxanone and polyglactin 910 had greater knot breaking strengths than Ethicon equivalents (P<.001). CONCLUSION Differences in mechanical properties exist between nominally identical suture materials from different manufacturers.

Efficacy of Postoperative Antimicrobial Use for Clean Orthopedic Implant Surgery in Dogs: A Prospective Randomized Study in 100 Consecutive Cases

OBJECTIVES To investigate whether administration of postoperative oral antimicrobial drugs has a beneficial effect on preventing surgical site infections (SSI) in clean orthopedic surgery involving stainless steel plating systems. STUDY DESIGN Randomized prospective clinical study. ANIMALS Dogs (n = 97). METHODS One hundred consecutive cases (97 dogs) that had clean orthopedic surgery requiring stainless steel plate fixation were randomly assigned using a random number generator to either YES group (administration of postoperative oral antimicrobials) or NO group (no administration of postoperative oral antimicrobials). Dogs in YES group were administered oral cefalexin or potentiated amoxicillin for 7 days, whereas dogs in NO group were discharged without oral antibiotics. Minimum follow-up was 12 months. Multivariable logistic regression was used to determine risk factors for SSI. RESULTS Overall postoperative infection rate was 12.9%. Infection occurred in 2 cases (4.3%) administered postoperative oral antimicrobials and in 10 cases (21.3%) not administered postoperative antimicrobials. Total anesthetic time and use of oral antimicrobials were the only significant factors associated with SSI. Use of postoperative antimicrobials was associated with a significant reduction in the risk of infection by ~84% and risk of infection was increased by ~2% for each minute increase in anesthesia time. CONCLUSIONS Administration of oral postoperative antimicrobials had a protective effect against development of SSI in clean orthopedic implant surgery.

The use of a stifle flexion device to manage avulsion of the lateral head of the gastrocnemius muscle in a cat

This report describes the diagnosis and treatment of a traumatic avulsion of the lateral head of the gastrocnemius muscle in a three-and-a-half-year-old male neutered Domestic Shorthaired cat. Surgical repair was achieved using a modified three-loop pulley suture pattern passed through a suture anchor inserted at the point of origin of the tendon and around the fabella. A stifle flexion device was utilised during the postoperative period to protect the repair. Follow-up at five months showed a return to normal function. This is the first report of avulsion of the lateral head of the gastrocnemius in a cat.

Single Transsacral Screw and Nut Stabilization of Bilateral Sacroiliac Luxation in 20 Cats

OBJECTIVE  This article aims to describe the use of a single transsacral screw and nut in a cohort of cats with bilateral sacroiliac (SI) luxation and document its radiographic and clinical outcome. METHODS  Medical records and radiographic studies of cats with bilateral SI luxation managed with a transsacral screw and nut stabilization were reviewed. Short-term follow-up included clinical examination and radiographs. Long-term follow-up was via owner questionnaire. RESULTS  Twenty consecutive cats with bilateral SI luxation were included. Six cats (35%) had additional musculoskeletal injuries that required stabilization. Luxations were stabilized with a single 2.7 cortical self-tapping transsacral screw and nylon nut (a metallic nut was used in one case). Postoperative radiographs confirmed SI reduction in all cats and a mean pelvic canal width ratio of 1.21 (a ratio of ≥1.1 was considered optimal). All cats available at follow-up examination were able to walk without signs of discomfort. Evaluation of follow-up radiographs showed maintenance of SI reduction and slight reduction of mean pelvic canal width ratio (1.18). Fourteen owner questionnaires were returned (median follow-up time of 40 months): nine cats were deemed to have normal activity and five cats were reported to have slight to mild reduced ability to jump or run. CLINICAL SIGNIFICANCE  The use of transsacral screw and nut stabilization of bilateral SI luxation in cats is a successful, repeatable and safe technique.