MRI of trunk muscles and motor and respiratory function in patients with myotonic dystrophy type 1

BMC Neurology

Table 5 Diameter and area of trunk muscles in 20 DM1patients and 20 controls

	DM1 patients		Controls		Difference
Muscles	Mean ± SD	Range	Mean ± SD	Range	t	p level	Cohens - d
a: Differences in muscle size for individual muscles. Adjusted p level = 0.005
Cranial rectus abdominis, mm	9 ± 2.5	4–14	12.3 ± 2.3	9–19	4.19	< 0.001	1.33
Caudal rectus abdominis, mm	10 ± 4.6	2–17	15.0 ± 3.7	10–27	3.55	0.001	1.12
External abdominal oblique, mm	8 ± 2.3	6–14	9.5 ± 2.9	5–15	1.28	0.208	0.35
Internal abdominal oblique, mm	8.3 ± 2.8	3–15	9.3 ± 2.0	6–13	1.09	0.281	0.41
Abdominal transverse, mm	3.6 ± 1.2	2–6	3.5 ± 1.1	2–6	0.14	0.893	0.04
Sum: oblique and transvers, mm	20.4 ± 4.7	14–32	22.3 ± 5.4	15–33	1.15	0.256	0.36
Psoas, mm²	1331.0 ± 372.5	752–2151	1436.7 ± 534.6	757–2605	0.73	0.473	0.23
Erector spinae L1/L2, mm²	1812.0 ± 433.7	989–2486	2106.0 ± 714.8	1242–3681	1.57	0.124	0.50
Erector spinae L3/L4, mm²	2069.3 ± 445.4	1471–3110	2391.2 ± 685.2	1252–4129	1.76	0.088	0.56
Erector spinae L5/S1, mm²	705.3 ± 351.7	0–1276	1010.1 ± 286.1	660–1576	3.00	0.005	0.95
b: Differences in muscle size for sum scores
Muscle size	DM1patiens		Controls		Difference
Muscles	Mean	Range	Mean	Range	p-level		Cohen’s d
Trunk flexors mm	40	(24–56)	50	(35–73)	0.002		1.05
Trunk extensors mm²	4587	(2727–6707)	5507	(3281–86,389)	0.030		0.71

Millimeter = mm, square millimeter = mm². The table displays the mean score, standard deviation and range, effect sizes d, and t with its p level are reported for each muscle

ISSN: 1471-2377