A multi-centre cohort study investigating the outcome of synovial contamination or sepsis of the calcaneal bursae in horses treated by endoscopic lavage and debridement

Multicenter study investigating long-term survival after synovial lavage of contaminated and septic synovial structures in horses presented to 10 UK referral hospitals

OBJECTIVE

To report the long-term survival of adult horses that were subjected to synovial lavage for treatment of contaminated and septic synovial structures.

STUDY DESIGN

Multicenter, prospective observational trial.

ANIMALS

Horses (n = 240) presented for synovial sepsis at 10 UK referral centers.

METHODS

Data for horses presented for treatment of synovial sepsis were collected over a 15 month recruitment period. Owners were contacted a minimum of 365 days after surgery using a structured client interview to assess long term survival. Descriptive statistics, and univariable and Cox proportional hazards models for postoperative survival time were developed.

RESULTS

Survival to discharge was 228/240 (95%) and overall long-term survival was 89.4% (185/207). Unknown cause of injury (p = .017), increasing duration of surgery (p = .003), increasing weight (p = .008), forelimb injuries (p = .027), and type of synovial structure (p = .008) were found to be associated with death using Cox proportional hazards models.

CONCLUSION

This study provides information on risk factors associated with survival and death after treatment for synovial sepsis at referral hospitals in the UK. Survival to discharge and long-term survival was excellent. Heavier horses, injuries affecting the forelimbs, tendon sheaths and bursae were associated with poorer long term outcomes. Longer duration of surgery was also found to be associated with a worse prognosis.

CLINICAL SIGNIFICANCE

These findings help to provide prognostic information for owners and veterinarians treating horses with synovial sepsis.

Regional antibiotic perfusion through the lateral saphenous vein in two horses with septic calcaneal osteitis

In this case report, two horses with chronic refractory infections in the tuber calcanei were successfully managed via intravenous antibiotic regional limb perfusion through the lateral saphenous vein after failure of conventional treatment approaches, including surgery and intravenous regional limb perfusion using the cranial branch of the medial saphenous vein. Surgical delay in these cases may have allowed the development of chronic infection, which prevented the conventional regional perfusion from working effectively. The spatial difference of the vessels relative to the tuber calcanei possibly contributed to the treatment outcome in these horses. This report describes a novel approach for regional antimicrobial perfusion to the equine plantar hock region using the lateral saphenous vein.

A scoping review of the current evidence on treatment and outcomes following synovial sepsis

BACKGROUND

Synovial sepsis is a frequent cause of morbidity and mortality in horses. Despite advances in diagnostics and treatments, persistent infection or chronic lameness can occur.

OBJECTIVES

To perform a scoping review to identify and evaluate the current evidence on the factors implicated in the success of treatment for synovial sepsis.

STUDY DESIGN

Joanna Briggs Institute scoping review.

METHODS

A protocol was registered, and a systematic literature search was performed on CAB abstracts, Medline, Scopus and Embase. Inclusion and exclusion criteria were developed and studies systematically reviewed against this. Studies relating to factors affecting treatment success following synovial sepsis were retained and data was extracted on study method, population characteristics and factors significantly associated with treatment outcome.

RESULTS

In total, 2338 studies were identified, and 61 were included to full paper analysis. Eight papers reported significant factors, identifying 15 risk factors associated with two measurements of outcome, either survival and/or return to athletic function. The 15 factors were identified and categorised into pre-, intra- and post-operative factors. Risk factors that were identified included the number or type of synovial structures involved, the presence of pannus, tendon and bone pathology, and the use of systemic antimicrobials. There were many discrepancies in inclusion criteria of cases of synovial sepsis as well as measurement and description of outcome variables.

MAIN LIMITATIONS

Non-English language studies or conference proceedings were not included. Only small numbers of papers had similar findings.

CONCLUSIONS

Standardisation of inclusion criteria is essential to enable comparisons and analysis between studies on synovial sepsis. Future studies should use methodologies to reduce bias including multicentre and multinational studies, prospective study design and robust statistical modelling.

Study design synopsis: Observational study design in equine research

When planning to conduct research, thorough consideration of the study design is essential to enable valid results and purposeful conclusions. A good study design will provide a strong basis for robust conclusions that can contribute to the evidence base. Conversely, a poor study design may unintentionally lead to invalid conclusions with inappropriate claims of the clinical importance. The purpose of this article is to review important aspects of observational study design, with an emphasis on observational clinical research. The value of an observational study can be manifold and the benefit of studying clinical cases can add substantial value to the evidence base and equine health and welfare, however this value will be diminished if study designs are flawed, or are inadequately reported. It is essential that clinicians have the skills to critically appraise observational studies, to determine strengths, limitations and the applicability to their clinical practice.