Dry Needling Produces Mild Injuries Irrespective to Muscle Stiffness and Tension in Ex Vivo Mice Muscles

Table 1

Number of fibers injured by puncture (LAL muscle).

	Healthy muscles	Muscles with MTrPs	Mimicking hypertonic muscles	Mimicking spastic muscles
Mean ± SD	4.2 ± 2.9	4.7 ± 1.7	5.6 ± 2.3	3.0 ± 1.1
		0.008	<0.001	<0.001
n of holes	225	195	225	135
95% intervals	3.9851; 4.4238	4.4913; 4.9959	5.3894; 5.9440	2.8730; 3.1714

Data expressed as the average number of fibers injured per hole created by the insertion of the needle ± SD. Fifteen insertions per LAL muscle and stained with methylene blue. In parentheses are the numbers of holes evaluated from 15 healthy muscles, 13 muscles with fibers with contraction knots, 15 hypertonic muscles, and 9 spastic muscles. Muscles submerged in a depolarizing Ringer solution (KCl, 20 mM) rich in calcium (CaCl₂, 5 mM) mimicking human muscles with hypertonia. Muscles submerged muscles in a Ringer solution with formalin (4%) mimicking spastic muscles. values were obtained by the Kolmogorov–Smirnov test and corresponds to comparison with respect to healthy muscles values.