Rib fractures in adult horses as a cause of poor performance; diagnosis, treatment and outcome in 73 horses.

BACKGROUND: Rib fractures in adult horses are poorly documented. OBJECTIVES: To describe the presenting signs, diagnosis, treatment and outcome of horses diagnosed with rib fracture. STUDY DESIGN: Retrospective case series. METHOD: The clinical records and diagnostic images of all adult horses diagnosed with a rib fracture at three referral centres over a 15-year period were reviewed. RESULTS: Seventy-three horses met the inclusion criteria. Horses presented due to either resistance to ridden work and poor performance (n = 41), lameness (n = 21) or trauma (n = 7). In four horses, the presenting complaint was not recorded. Clinical assessment and palpation localised the site of injury in 18/47 cases where recorded. Nuclear scintigraphic examination identified all fracture sites in which it was performed (59/59). In 10/24 horses, radiographic examination confirmed rib fracture. Ultrasonographic examination confirmed rib fracture in 58/59 horses (98%; 95% CI 92-100). Six horses underwent surgery due to ongoing clinical signs and non-healing fracture; all other horses were managed conservatively. Fifty-five horses were available for long-term follow up (>1 year), of which 28 (51%; 95% CI 38-64) returned to their previous level of exercise. Twelve horses did not return to their previous level of exercise due to lameness unrelated to the rib fracture and seven horses were subjected to euthanasia, of which three were as a result of the rib fracture. Eight horses did not return to their previous level of exercise for other reasons. MAIN LIMITATIONS: Incomplete data set due to retrospective case series. CONCLUSIONS: Although uncommon, rib fractures should be considered in cases of reduced performance or resistance during ridden exercise. Palpation may be unrewarding. Scintigraphy and ultrasonography are useful in identifying the fracture site. Rib fractures in horses carry a fair prognosis and can be managed conservatively in most cases.

Mineralization of the Equine Palmar/Plantar Annular Ligament Treated by Surgical Resection.

OBJECTIVE: To document the clinical presentation, diagnosis, and surgical treatment of mineralization of the equine palmar/plantar annular ligament (PAL). STUDY DESIGN: Retrospective study. ANIMALS: Ponies (n=7). METHODS: Case records from 2 referral hospitals were examined to identify cases with lameness associated with PAL mineralization treated surgically. Follow-up information was obtained from the owners by telephone questionnaire. RESULTS: Duration of lameness before referral ranged from 5 weeks to 6 months, and degree of lameness from grade 1 to 5 out of 10. In 3 cases, records noted obvious pain when pressure was applied over the PAL. Pain resulting in lameness was localized to this area and all cases were treated surgically, although the extent of resected tissue varied among cases. Histological examination of resected tissue (4 cases) revealed fibrocartilaginous and/or osseous metaplasia. Following surgery, 6 of the 7 ponies became sound. CONCLUSION: Based on this limited case series, surgical treatment for mineralization of the PAL offers a favorable success rate without severe complications where conservative methods have failed.

Multistate outbreak of Listeriosis linked to turkey deli meat and subsequent changes in US regulatory policy.

BACKGROUND: Listeriosis, a life-threatening foodborne illness caused by Listeria monocytogenes, affects approximately 2500 Americans annually. Between July and October 2002, an uncommon strain of L. monocytogenes caused an outbreak of listeriosis in 9 states. METHODS: We conducted case finding, a case-control study, and traceback and microbiological investigations to determine the extent and source of the outbreak and to propose control measures. Case patients were infected with the outbreak strain of L. monocytogenes between July and November 2002 in 9 states, and control patients were infected with different L. monocytogenes strains. Outcome measures included food exposure associated with outbreak strain infection and source of the implicated food. RESULTS: Fifty-four case patients were identified; 8 died, and 3 pregnant women had fetal deaths. The case-control study included 38 case patients and 53 control patients. Case patients consumed turkey deli meat much more frequently than did control patients (P = .008, by Wilcoxon rank-sum test). In the 4 weeks before illness, 55% of case patients had eaten deli turkey breast more than 1-2 times, compared with 28% of control patients (odds ratio, 4.5; 95% confidence interval, 1.3-17.1). Investigation of turkey deli meat eaten by case patients led to several turkey processing plants. The outbreak strain was found in the environment of 1 processing plant and in turkey products from a second. Together, the processing plants recalled > 30 million pounds of products. Following the outbreak, the US Department of Agriculture's Food Safety and Inspection Service issued new regulations outlining a L. monocytogenes control and testing program for ready-to-eat meat and poultry processing plants. CONCLUSIONS: Turkey deli meat was the source of a large multistate outbreak of listeriosis. Investigation of this outbreak helped guide policy changes designed to prevent future L. monocytogenes contamination of ready-to-eat meat and poultry products.

Molecular surveillance of shiga toxigenic Escherichia coli O157 by PulseNet USA.

PulseNet USA is the national molecular subtyping network system for foodborne disease surveillance. Sixty-four public health and food regulatory laboratories participate in PulseNet USA and routinely perform pulsed-field gel electrophoresis of Shiga toxigenic Escherichia coli isolated from humans, food, water, and the environment on a real-time basis. Clusters of infection are detected in three ways within this system: through rapidly alerting the participants in the electronic communication forum, the PulseNet Web conference; through cluster analysis by the database administrators at the coordinating center at the Centers for Disease Control and Prevention of the patterns uploaded to the central server by the participants; and by matching profiles of strains from nonhuman sources with recent human uploads to the national server. The strengths, limitations, and scope for future improvements of PulseNet are discussed with examples from 2002. In that year, notices of 30 clusters of Shiga toxigenic E. coli O157 infections were posted on the Web conference, 26 of which represented local outbreaks, whereas four were multistate outbreaks. Another 27 clusters were detected by central cluster detection performed at the Centers for Disease Control and Prevention, of which five represented common source outbreaks confirmed after finding an isolate with the outbreak pattern in the implicated food. Ten food isolates submitted without suspicion of an association to human disease matched human isolates in the database, and an epidemiologic link to human cases was established for six of them.