Anatomical position of the palmar/plantar nerves at the metacarpal/metatarsal distal level in horses: An in vivo study by means of ultrasonography.

The neurovascular bundle of the equine distal cannon can dynamically vary with limb position, and this can affect the performance of low 4- or 6-point block. This study aims to identify and describe the anatomical position and variations of the lateral and medial palmar/plantar nerve at the metacarpal/metatarsal distal level in horses by ultrasonography. Eight mares underwent ultrasound examination on the lateral and medial palmar/plantar sides of the metacarpus/metatarsus. Images were obtained for measurements of the cross-sectional area of the nerve, distances between the nerve and the skin surface, branch of the suspensory ligament (SL), deep digital flexor tendon (DDFT) and superficial digital flexor tendon (SDFT) with limbs supported and elevated. The distance to the skin for forelimbs was higher on the lateral side when the limb was elevated (p < 0.001). The comparisons between supported and elevated limbs on the same side showed longer distances to the skin with the limb supported on the medial side (p < 0.001). Hindlimbs showed longer distances to the skin with the limb supported on the medial face (p = 0.027). The anatomical position of palmar/plantar nerves was similar between the lateral and medial sides of the limb, generally being in contact with the dorsal edge of DDFT. The strategy of elevating the limb during the injection of the low 4- or 6-point block can lead to a higher risk of puncture of the digital sheath.

Effects of medical ozone upon healthy equine joints: Clinical and laboratorial aspects.

OBJECTIVE: The aim of this study was to verify whether transient inflammatory reactions induced by intra-articular medicinal ozone administration affect joint components, by in vivo evaluation of inflammatory (prostaglandin E2, Substance P, Interleukin-6, Interleukine-1, Tumor Necrosis Factor), anti-inflammatory (Interleukin-10) and oxidative (superoxide dismutase activity and oxidative burst) biomarkers and extracellular matrix degradation products (chondroitin sulphate and hyaluronic acid) in synovial fluid. METHODS: The effects of medicinal ozone were analyzed at two ozone concentrations (groups A and B, 20 and 40 µg/ml, respectively), using oxygen-injected joints as controls (group C); each group received ten treatments (15 ml gas per treatment). Physical evaluation, evaluation of lameness, ultrasonography, and synovial fluid analysis were performed. RESULTS: All joints presented mild and transient effusion throughout the study. Group B exhibited the highest lameness score on day 14 (P<0.05), detected by the lameness measurement system, probably because of the higher ozone concentration. All groups exhibited increased ultrasonography scores on day 14 (P < 0.05). Groups A and B exhibited increased proteins concentrations on day 21 (P<0.05). There was no change in hyaluronic acid concentration or the percentage of high-molecular weight hyaluronic acid throughout the experiment. Chondroitin sulfate concentrations decreased in group B, and did not change in group A and C, indicating that neither treatment provoked extracellular matrix catabolism. Cytokine and eicosanoid concentrations were not significantly changed. CONCLUSIONS: The ozonetherapy did not cause significant inflammation process or cartilage degradation, therefore, ozonetherapy is safe at both evaluated doses.