Effect of needle brand, needle bevel grind, and silicone lubrication on contamination of joints with tissue and hair debris after arthrocentesis.

OBJECTIVE: To assess contamination of joints with tissue and hair debris after arthrocentesis. STUDY
DESIGN: Experimental. ANIMALS: Fetlock joint tissues (n = 6 horses).
METHODS: Soft tissue flaps including joint capsule were dissected from the dorsal aspect of fetlock joints of 6 anesthetized horses leaving an intact proximal base ("live" model) or with complete excision and immediate mounting to a wooden frame ("fresh" model). Needles were inserted through joint tissues and saline solution was flushed through them into tissue culture plate wells, and then examined for tissue and hair debris. Nine needle types were assessed; variables included needle brand, needle bevel grind, needle size, and silicone lubrication.
RESULTS: No significant difference was detected between "live" and "fresh" models for hair or tissue contamination. Compared to 20 g hypodermic needles, 19 g lubricated and 19 g non-lubricated needles had a significantly greater odds ratio (OR) for hair contamination. Nineteen-gauge non-lubricated needles had a significantly greater OR for hair contamination than 19 g lubricated needles. No significant differences in ORs were identified between type of needle bevel grind, brands of disposable hypodermic needles, or brands of spinal needles for hair or tissue contamination.
CONCLUSIONS: Nineteen-gauge needles significantly increase the risk of joint contamination with hair compared to 20 g needles; non-lubricated 19 g needles have the greatest risk. All other needle types tested in this study have similar risks for tissue and hair contamination after arthrocentesis. © Copyright 2014 by The American College of Veterinary Surgeons.