Aziz Tnibar

Changes in concentrations of haemostatic and inflammatory biomarkers in synovial fluid after intra-articular injection of lipopolysaccharide in horses

BackgroundSeptic arthritis is a common and potentially devastating disease characterized by severe intra-articular (IA) inflammation and fibrin deposition. Research into equine joint pathologies has focused on inflammation, but recent research in humans suggests that both haemostatic and inflammatory pathways are activated in the joint compartment in arthritic conditions. The aim of this study was to characterize the IA haemostatic and inflammatory responses in horses with experimental lipopolysaccharide (LPS)-induced joint inflammation. Inflammation was induced by IA injection of LPS into one antebrachiocarpal joint of six horses. Horses were evaluated clinically with subjective grading of lameness, and blood and synovial fluid (SF) samples were collected at post injection hours (PIH) -120, −96, −24, 0, 2, 4, 8, 16, 24, 36, 48, 72 and 144. Total protein (TP), white blood cell counts (WBC), serum amyloid A (SAA), haptoglobin, iron, fibrinogen, thrombin-antithrombin (TAT) and d-dimer concentrations were assessed in blood and SF.ResultsIntra-articular injection of LPS caused local and systemic signs of inflammation including increased rectal temperature, lameness and increased joint circumference and skin temperature. Most of the biomarkers (TP, WBC, haptoglobin, fibrinogen and TAT) measured in SF increased quickly after LPS injection (at PIH 2–4), whereas SAA and d-dimer levels increased more slowly (at PIH 16 and 144, respectively). SF iron concentrations did not change statistically significantly. Blood WBC, SAA, haptoglobin and fibrinogen increased and iron decreased significantly in response to the IA LPS injection, while TAT and d-dimer concentrations did not change. Repeated pre-injection arthrocenteses caused significant changes in SF concentrations of TP, WBC and haptoglobin.ConclusionSimilar to inflammatory joint disease in humans, joint inflammation in horses was accompanied by an IA haemostatic response with changes in fibrinogen, TAT and d-dimer concentrations. Inflammatory and haemostatic responses were induced simultaneously and may likely interact. Further studies of interactions between the two responses are needed for a better understanding of pathogenesis of joint disease in horses. Knowledge of effects of repeated arthrocenteses on levels of SF biomarkers may be of value when markers are used for diagnostic purposes.

Medial patellar ligament splitting in horses with upward fixation of the patella: A long-term follow-up

REASONS FOR PERFORMING STUDY Medial patellar ligament splitting (MPLS) has been shown to be a highly effective and minimally invasive treatment for upward fixation of the patella (UFP) in horses. However, long-term follow-up results of this procedure have not previously been reported. OBJECTIVES To evaluate the long-term resolution of UFP following MPLS and provide information on complications and recurrence. STUDY DESIGN Retrospective case series. METHODS Data were collected from horses that underwent MPLS between 1999 and 2013. All cases had a confirmed diagnosis of UFP that had not responded to conservative therapy. Data were collected from medical records, including follow-up visits and through telephone conversations with the owner, trainer or referring veterinarian. RESULTS A total of 85 horses were included. Fifty-eight horses (68%) had surgery under general anaesthesia in dorsal recumbency, while 27 horses (32%) underwent standing surgery and 97.6% had complete resolution of the UFP immediately after surgery or within the 2 week rehabilitation period. Two cases (2.4%) had only unilateral resolution after bilateral surgery, even after the procedure was repeated. The majority of cases (90.5%) were followed up at least 3 and up to 14 years after surgery. No short- or long-term complications were reported. No recurrence of UFP was observed in the horses that resumed exercise after surgery. CONCLUSIONS Medial patellar ligament splitting is a highly effective and minimally invasive surgical procedure to treat UFP when conservative treatment is unsuccessful. In addition, it allows for a very rapid return to sports activity. No short- or long-term complications were observed and no recurrence of this condition was noted.