Arthroscopically accessible anatomy of the tarsal collateral ligaments in the horse.

OBJECTIVE: To describe the arthroscopically accessible anatomy of the tarsal collateral ligaments in the horse. STUDY DESIGN: Descriptive study. ANIMALS: Cadaveric equine hind limbs (n = 24) obtained from horses without tarsal disease. METHODS: Two pairs of tarsal joints were used to obtain silicone models of the tarsocrural joint and dissect the tarsal collateral ligaments (CLs). Ten pairs of tarsocrural joints had arthroscopic exploration and the accessible parts of the tarsal CLs were marked with an arthroscopic hook knife. Subsequently, the limbs were dissected and the marked positions were allocated to the specific parts of the CLs. RESULTS: Ipsilateral arthroscope and instrument portals were used in each pouch of the tarsocrural joint. Via the plantaromedial pouch, the superficial (2/20 limbs), middle (7), deep (6) or both middle and deep (3) short medial CL and the long medial CL (14) were reached. Access via the plantarolateral pouch allowed manipulation of the deep short lateral CL (20/20 limbs) and the long lateral CL (20). Dorsally, arthroscopy via the dorsomedial pouch gave access to the deep short medial CL (20/20 limbs), while the superficial (9) or middle (10) or both superficial and middle (1) short lateral CL could be reached via the dorsolateral joint recess. CONCLUSIONS: Limited parts of the tarsal CLs can be observed or manipulated arthroscopically in normal equine tarsocrural joints.

Locking compression plate osteosynthesis of sacral fractures in three heifers.

OBJECTIVE: To describe a technique used for reduction and internal fixation of sacral fractures in cattle. STUDY DESIGN: Case series. ANIMALS: Three heifers aged 19-32 months with deformation of the tail head and tail paralysis attributable to a closed fracture of S5 or S4 and S5. METHODS: Fractures were reduced and repaired under general anesthesia. A narrow, 6-10-hole, locking compression plate (LCP) was placed on the spinous processes of S5 and the first coccygeal (Co1) using 5.0 mm locking head screws. Follow-up inquiries were made by telephone (3/3), and cows were examined clinically and radiographically 2 (1 cow) to 9 (1 cow) months postoperatively. RESULTS: No complications were encountered. The range of movement of the tail improved so that soiling of the tail during defecation was no longer a problem. In all heifers, the normal top line was restored and there was no narrowing of the pelvic canal. Unassisted calving occurred in all heifers, and follow-up radiographs for 2 cows showed complete fracture healing. CONCLUSION: LCP-osteosynthesis of the spinous processes provided sufficient stability for internal fixation of sacral fractures. Marked improvement in tail function occurred postoperatively without decompression by laminectomy.